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A: Turn-1 Plays (4)
B: Turn-2 Plays (12)
C: Turn-3 Plays (8)
D: Situational Spells (12)
E: Fetchlands (10)
- 1x Bloodstained Mire
- 1x Flooded Strand
- 1x Marsh Flats
- 1x Misty Rainforest
- 4x Polluted Delta
- 1x Scalding Tarn
- 1x Verdant Catacombs
F: Fetch Targets (6)
The aim of this page is trying to determine the best Glimpse the Unthinkable-based strategy available in Modern, and design the optimal list accordingly; budget is not a concern. That is, my primer wants to get the most out of a Mill deck (hence the label 'competitive'). This article is long because it is meant to be complete and thorough, not appealing: you are free not to read it if you think you don't need to.
Test sessions and theoretical brooding have led me to surmise that Mill could ever hardly do better than this; I might look presumptuous or arrogant, but I'm not, since I'm taking full responsibility for what I say here. I will unfurl a primer below, trying to give explanation; but if I took something inappropriately for granted, I will surely make plain upon request. Anyway, I will try to be thorough in expounding the reflections that took me to such conclusion.
Building Mill in Modern
Starting from perusing and sifting through the Modern pool so as to form an idea of what it can offer in order to build a Glimpse the Unthinkable-based deck focused on milling the opponent out, in this section I will rough-out this strategy's possibilities. What am I doing here is merely/mostly reporting the outcome of a process fundamentally got at via multiple cycles of mutual adjustment between the cards which can be helpful to the strategy on one hand, and what the strategy itself needs in its many aspects on the other.
It is reasonable, before anything else, to explore and probe what a dedicated mill can accomplish when unchecked. In order to do so, I will display the viable mill-spell options, catalogued by CMC (Casting Mana Cost) and arranged by milled-cards/CMC ratio (expressing how many cards they mill for spent mana). Because the cards position in the list regards the milling performance, for cards not milling per se I consider them as having attained something when they return value in form of milled cards - or when they allow you to cast an effective mill spell such as Glimpse the Unthinkable in a timely fashion. I will be obvious in commentig obviously bad cards, but they can be hidden gems if our needs - mostly a function of the metagame - change in a particular way and it can be useful debating exactly where they are strong enough to see play. You can surely skip this part if you are acquainted with Modern mill spells.
Archive Trap: if your opponent plays a 'low' (for our purposes) number of fetchlands (say, 7 - which is very realistic in a fair Modern deck), it is not quite reliable to cast for 0 mana: dangerous decks (Infect, Zoo, even Jund!) can deploy their threat with only 2 mana, often allowing them to need not to search for the entire game (not every land is a fetchland!). After their turn 2 we lose quite any chance of casting Archive Trap for 0: in order to minimize the chances of drawing it late, again, adopting a turbo-mill plan that tries to win as early as possible finds here another reason for consideration. Weren't this enough, a lot of decks don't play fetchlands at all, and other potential searching effects (like Chord of Calling) can be left unused until they can win right away. In addition, casting it at 5 mana is unaffordable if not against decks you are already heavily favoured: slow decks. BUT overall, given the options, it is one of the most effective 'defences' against (most) fast decks, allowing us to close the game earlier: Archive Trap lets you literally race against fast decks. Regarding Archive Trap not being reliable, I want to remark that more or less randomness is part of the game - and that everything, in this game, can be calculated in terms of probability (and consistency be estimated on those bases); a Magic card in a deck should be evaluated on the influence it has on the overall winning percentage, not on the fact that it is a dead card in a given number of occasions; in addition chances are that Mill, not being a control or a midrange deck, doesn't really rely on card or value advantage - unless the overall card quality were so low that you couldn't win without it: it should afford some dead draw. Now, I'd like to make a comparison and with that eliciting a reflection: even a bad card like Fog in an aggro deck like Zoo can be game-breaking: it can make the caster win the race against another aggro; but it doesn't mean that this would be a good plan to execute in general, because reaching that particular situation is quite rare and difficult to achieve, and in other situations that card isn't quite of any use. In Mill the card that most resembles Fog in the depicted situation is not a fog itself - because a deck emplying them would be designed to make those cards quite strong (and even to often require them!); but Archive Trap. Nonetheless, I assume that searching is an action executed widespreadly enough to make them more worth than the Fog in the previous example is in its situation; also Archive Trap is a 'necessary evil', because the opportunity cost is quite low against fast decks (there are hardly good enough replacements in that slot, even if conceived as 'defensive' ones). Still, it surely isn't a good late-game draw by any means - thus also taking a little effectiveness off of Visions of Beyond if Archive Trap is drawn with it - but that liability now is more or less mitigated by Field of Ruin, but it is still a 2-card combo. However, we tend to disregard the fact that if our opponent has no/too few means to search her library and no/too few non-basic lands we must give up an important piece of our deck in Archive Trap (that we should play regardless): this totally adds up, increasing the number of dead cards. And Archive Trap is not really replaceable with sideboard cards, even if we try to do it nonetheless.
Chancellor of the Spires: as for the previous card, the conditions to achieve the effect of this card can be accounted for as factors in computing the average mill-power: thus the position in the list.
Surgical Extraction: it can indeed be used merely as a mill card - even though a very ineffectual one.
Hedron Crab: it can win the game nearly on its own if uncontested. Bonus milling when combined with fetchlands. Playing a land immediately after it has resolved (we get priority again, if it's our turn and the stack is empty) allows us to mill 3 (or more) unopposedly: this means that if the hand has a low spell count, Hedron Crab had better be held in hand and played on turn 2 before the land (if slowing the game is affordable: sometimes, against fast decks mostly, it is overall safer to cast it on turn 1 and hope to draw something like a 2-mana spell the very next turn). Unlike Ensnaring Bridge, I won't be in much pain if they remove it: the list is very redundant on mill spell, and here the ceiling is very high - the floor being still quite good, especially because it can net value before dying and demands a very early removal: unlike Mesmeric Orb, which takes its time to be effective, Hedron Crab makes value even in the early stage of the game - so if they remove it, they do that instead of playing threats, resulting in a huge time loss in our favor. In any case, even a single Hedron Crab is enough to put us in good shape: it is the best card in the whole deck by a huge margin. In the end, Hedron Crab is not a good turn 1 play, BUT (1) mana constraints are a pressing matter, so that cantrips end up being bad since we not searching anything specific (unlike combo) and we have no mana to spare (unlike control); (2) spot removals like Fatal Push are quite useless in Mill, so they can hardly cover the 1-mana slot (though we might need to play a few of them nonetheless for tempo purpose and because of the low quality of the alternatives); (3) discards or counterspells generally do not solve any of our problems; (4) there isn't any other 1-mana Mill spells you want (or, worse, need) to play, and on the opposite the 2-mana+ slots are choked: so you really need to open up with Hedron Crab a lot of times (you will certainly save it for later against midrange or control, for instance).
Shriekhorn: since slow strategies are mostly easy match-ups and in any case Mill win expectation does not depend on the mill spells quality, Shriekhorn is (for what it's worth) better than any Codex Shredder-like card, because the game against fast decks should not last more than 4 turns anyway (5 or more if covered by fogs). If Shriekhorn is drawn in the first stages of the game, it's a 'mill 6 for 1 mana' spell, which is quite strong for a 1-mana mill spell; if it is drawn late, Mill generally doesn't care because it has a lot of relevant action to play out in mid- or late-game (at least against the frightening aggro decks): Mill is so slow that you will surely have mill spells to play on turn 4, and that is also why Shriekhorn taking turns to do its work is not a real problem: later in the game we will cast our expensive spells still in hand. Also along the game it is not rare that the mana left available for our 1-mana spell is nonblue (because of a Field of Ruin or a Swamp), and that late Shriekhorn turns out to be often better than another spells we couldn't cast. Though it is usually bad to spend a removal on Shriekhorn, it is a matter of consideration; on the other side, Shriekhorn doesn't get countered by Cursecatcher or Glen Elendra Archmage. In addition, like Hedron Crab Shriekhorn works perfectly with Set Adrift from the sideboard (turning it on early without spending two whole card - one to mill ourselves and one to mill their threat); and it is useful to have mill effects that are cheap (e.g. for milling away the card targeted by Set Adrift) and instant (e.g. to win against Academy Ruins, in conjunction with Shelldock Isle + any mill spell, or Hedron Crab + a fetchland, or Archive Trap, or simply Field of Ruin), and this card covers both those roles. Essentially, what really sets it apart from Tome Scour is that Shriekhorn is good with Set Adrift, can let you draw 3 from Visions of Beyond alongside a lone Archive Trap (13+1+6=20), and mills 1 more card when needed (that is, when you play it early).
Minister of Inquiries: the issue with this card is that when it is bad (no good block/no block at all/block irrelevant/dies immediately..) it is really, really bad since it doesn't give any sort of residual advantage (the energies left are useless: following Minister of Inquiries will suffer the fate of the first) or it is too slow; for what it matters, people are more prepared to deal with it than to deal with with Shriekhorn. All this while the ceiling is quite mediocre: best case scenario, it is as effective as one of the worse mill cards (Shriekhorn) with a bonus chumpblock - though the fact Minister of Inquiries could block in a pinch is irrelevant (as with any creature we could play: see below) since all the decks wanting to attack with creatures have their way to deal with blockers (trample, unblockable, removals..). One should not play Minister of Inquiries unless wanting to go really deep in 1-CMC mill cards (which I do not recommended).
Tome Scour: unlike Shriekhorn, it is useful in late-game also - as much as it matters. The flaws with Minister of Inquiries and the negligible (other reasons accounted for) difference in mill-power are the reasons why is usually better to play the fullset of Tome Scour before playing the first copy of Minister of Inquiries unless willing to go deep with Fraying Sanity (which bodes ill for your success..).
Memory Sluice: in a mill-oriented deck full of creatures and in a metagame without removals it would be very good!
Thought Scour: see the following entry.
Broken Ambitions: it is included here because for efficiency reasons it can even be used with X=0 just for milling - which I consider for ease happening half of the times in fast games (that is, where we want to evaluate the impact of cards for a clunky deck like Mill); like Thought Scour it exchanges two milled cards for 1 mana and the card itself, and situationally converts extra mana (to counter or to cast the drawn spell in case) for one additional card (drawn and cast, or countered)).
Glimpse the Unthinkable: the card this deck is built around; because playing it is a principled assumption (it's the aim of the deck), technical comments or justifications are invalid: so I'll stress instead on how beautiful the picture is. :D
Mesmeric Orb: this mills differently accordingly to the turn in which it is played, the opponent's deck and the game state; I believe that this is the right position for it, as in general it is better than the alternatives below in the list. Like Manic Scribe, it needs a lot of work to be effective (so it is not the best card to hope for in general): it works very very well with fog-effects, but sometimes it requires a fog-investiment (hoping the opponent tries to win via (many) creatures attacking) to take the game where needed (that is to 'activate' Visions of Beyond and Shelldock Isle); if this happens, then another fog-effect is to be retrieved as soon as possible for the imminent 'moment of need'. Like Ensnaring Bridge, it is soft to incidental artifact/permanent hate; also the opponent will surely board in artifact hate in place of the many useless cards (the removal kind, or some 'value-engine'..), and in those games it may mill nothing (especially against a milled Ancient Grudge). If played late, it is generally a very bad mill spell since the opponent could just attack only with enough creature to threaten leatal unless they knew you are planning to attack their plan from a different angle with Damnation or Crypt Incursion. These are the cons. The pros are that all in all it is the best-performant mill spell at 2 mana behind Glimpse the Unthinkable - and when played early it is even better! Cast in the first stages of the game against an aggro deck that would demand fog-effects anyway, or if it manages to dodge counterspells against (a no-Emrakul, the Aeons Torn-)control, it warrants us a very good position (for this deck standards at least); additionally, it really really really shines against Affinity and Elves: in general, it is very good at catching up with decks attempting to go wide. All in all, considering that it grants an easy time against some decks and that casting it later than on turn 2 (say, you start the game with two copies in hand), unless it is the very last turn of the game, it is sometimes better than the next 2-CMC mill spell in a quality-scale (Breaking / Entering), playing 4 Mesmeric Orbs is recommended. It gets better with 1-mana mill spells (though the deck hardly wants any of them) since it takes a while to mill a critical amount of cards: 1-mana mill spells get us to have earlier Visions of Beyonds, Shelldock Isles and Crypt Incursions so that at that point Mesmeric Orb will be able to work at its full potential (i.e. snowballing from early to late game).
Breaking / Entering: even if it leaves you with a Glimpse the Unthinkable feeling, you may want to turn your nose up at a card worth 80% of Glimpse the Unthinkable. Mill happens to care about milling only by tens: you'll never have to mill much lesser than 50, and many of your engines begin to work at 20 (Visions of Beyond) and 30 (Shelldock Isle) milled cards. As opposed to most mill spells you'll want to play, it doesn't achieve the 10+ milled cards per spell the deck needs in order to efficiently (as to mana/cards) enable Visions of Beyond (2 spells), Shelldock Isle (3 spells) and victory itself (5 spells); and all that matters a lot especially in the mid game when you couldn't cast Archive Trap for free, it's too early for harvesting profits for Mesmeric Orb, you had a bad Mind Funeral milling or your Hedron Crab died early. Sometimes you get lucky with your Breaking / Entering because your opponent have thinned her own deck or because you compensate your lucklaster spell in Breaking / Entering with another card (e.g. Archive Trap); but that goes a long shot from cover all the cases. And when you are forced to cast a second Breaking / Entering, you'll probably lose anyway. If you think you're saving 1 mana replacing Mind Funeral with Breaking / Entering, you're deluding yourself: many times you'll find yourself needing to cast an additional spell to win, and that will cost you a card and more mana. Even if we could use some mill spell to round the mill count for Visions of Beyond or Shelldock Isle, Breaking / Entering definitely costs too much for it to be its only role! A little trick is casting the Entering side (note: only that of course!) via Shelldock Isle, in order to provide a blocker or perhaps responding to Emrakul, the Aeons Torn's trigger (this could also be the only way out against a Progenitus in the whole deck, if it will ever exist the possibility of encountering it, even though it would still be a losing proposition in any case).
Compelling Argument: too much inefficient, and you don't really wanna spend your mana cycling not even with the intent of keeping few-landers this way since this clumsy deck cannot afford it.
Manic Scribe: it needs a lot of work to be effective: it conceivably would require you to play a great amount of cards we wouldn't normally want to play and that would twist the main plan too much - like the following: Manamorphose, Street Wraith, Mishra's Bauble, Jace's Phantasm, Minister of Inquiries, Death's Approach, Spontaneous Mutation. The latter two are solid removal spell which also work towards getting delirium; unfortunately, removals are quite uneffective in a mill strategy (more below). And if you play a lot of cyclers sure, you can trim some lands, but ultimately you have to cut spells too: the remaining spells had better to be high-quality ones, and Manic Scribe is too easily foiled while if it manages to stay on the battlefield with delirium active the reward is not so appealing overall (it even needs some turns to do something better than the alternatives!). As for coupling it with Mesmeric Orb, you need to keep in mind that Manic Scribe curves out poorly into it and vice versa: if you play the artifact on turn 2, you cannot block early creatures (losing part of the effectiveness of Manic Scribe itself: how much defence or how many game-prolonging measures can a Mill deck have?); if you play the creature, on the other hand, you mill less cards from Mesmeric Orb - and, as an important consequence, failing to prime Manic Scribe, an early triggering of which is mostly the main reason reason to run Mesmeric Orb in a Manic Scribe-list (as Mesmeric Orb requires fogs to work effectively, not defences in the form of creatures - or removals, for argument's sake): in this case, Manic Scribe is to be reckoned a mill spell (a very bad one) with minor upside for being able to block. But Manic Scribe cannot cover a relevant defensive role due to the issues it shares with Jace's Phantasm or Wight of Precinct Six as creatures in this deck (more below) (note that Hedron Crab is played regardless of those consideration because of the stratospheric power level, and because it is almost exclusively a mill spell). All in all, Manic Scribe is a very bad card that gets only mediocre if supported by other cards, which unfortunately are incidentally quite bad in Mill - as useful as it is when it blocks revevantly and against Leyline of Sanctity.
Fraying Sanity: this card counts both as a mana and card-advantage engine: the first mill spell following it will fully repay the expense in mana and cards sustained for playing Fraying Sanity; any mill spell after that will but net great advantages - even though most of the times the second one will close the game out already, making Fraying Sanity already great as it is. Bear in mind that Fraying Sanity does not double up the mill count of Manic Scribe, Mesmeric Orb and (frequently) Shelldock Isle the turn you intend to win; however, it gets you additional mills for each of their sorceries, instants or fetchlands; only be sure to take Fraying Sanity out if bringing in Leyline of the Void. Overall, the benefits of playing Fraying Sanity are (1) almost assured turn 5 wins and (2) more proper turn 4 wins as to the ones not requiring Fraying Sanity (and now that we get the Field of Ruin combo, at times Fraying Sanity just becomes non-sensical!).
Mind Funeral: much like Mesmeric Orb, it mills a lot when needed - that's to say against fast decks (often running relatively few lands) - thus hopefully shortening the lenght of the game compared to what would happen with playing another kind of mill spell. Again like Mesmeric Orb, it is quite an unreliable mill spell (it could mill only 4 or more than 20 alike), but overall the odds are fine - as shown by the below results, provided by a computer simulation outputting the average milled cards over 1 million Mind Funeral castings against a deck featuring a given number of lands. Also, it is possible to sequence mill spells so as to cast Mind Funeral when there is a high percentage of the opponent's lands in the graveyard (or known as not in the library, anyway); or to cast Surgical Extraction targeting lands played in many copies: either way, a greater-than-normal milling will ensue more likely than not. However, the fact that your opponent may lower her land count by cracking fetches or because of our Path to Exiles, Ghost Quarters, Field of Ruin or Surgical Extractions shouldn't exert much allure, as it is not enough to make Mind Funeral much stronger - as the calculations suggest: for instance, Mind Funeral mills about 11 against a 20-land deck like Burn; if we take them to have, say, 2 lands less in the deck every single game (very realistic in normal games, especially if your deck forces in that direction by means of the like of Path to Exile), then we will mill around 12 cards: only 1 card more!!! Only note that against fast decks, even if Mind Funeral especially overperformes against them, you don't have time to cast many high drops; and that versus slower decks, Mind Funeral is quite bad due to their high land count. All in all, in most circumstances you cannot afford to set up a big-milling Mind Funeral (waiting for their 'known lands'/'known cards' to be grater than lands/cards ratio of their maindeck, either via natural milling or with cards such as Ghost Quarter) as you need to cast Mind Funeral the first time you have the chance to do that - especially for curve (i.e. efficiency, and thus speed) purpose; this, which is undeniably a drawback, incidentally entails a little benefit in that computing ratios at every change of the game-state would be really wearying (a consideration for big tournaments, of the kind already examined regarding Surgical Extraction).
Maindeck Lands__Milled Cards
16_ _ _ _14.35
17_ _ _ _13.55
18_ _ _ _12.84
19_ _ _ _12.19
20_ _ _ _11.62
21_ _ _ _11.09
22_ _ _ _10.61
23_ _ _ _10.17
24_ _ _ _9.76
25_ _ _ _9.38
26_ _ _ _9.05
27_ _ _ _8.72
Sanity Grinding: in order to give loosely the same performance as Mind Funeral, the deck has to feature an average of 1 blue mana in the casting cast of each single card; if the deck contains, say, 20 lands, it's about 1,66 per single spell: this is something difficult to achieve even in a monoblue deck - and preposterous in Modern. And if you play 1-mana spells, that means that you are loaded of double- and triple- mana costs: clumps of blue costs will be more frequent, further decreasing your change to get a good mill with it.
Ashiok, Nightmare Weaver: good against midrange with a not-so-good power/mana ratio (this excludes Tarmogoyf-decks: it is good to steal a Tarmogoyf, but it is also bad to have Ashiok, Nightmare Weaver die from a single Tarmogoyf attack), but even then its use would be too narrow and too little effective to be worth of consideration. And hoping to ride it to victory against Emrakul, the Aeons Torn decks is preposterously unreliable, of course.
Startled Awake : even if Mill needed 4-drops, there are better options.
Trapmaker's Snare: in sideboarded games, it can search for traps like Ravenous Trap (which is already very reasonable on its own), Mindbreak Trap (a tool against Storm), Lethargy Trap, Whiplash Trap, Permafrost Trap (the lasts ones are not good though). It is not so useful for getting an Archive Trap if not in a dedicated deck, since Archive Trap is already underwhelming as it is (more below); I would never play a card planning to use it often times only for getting that effect overcosted by 2 mana. I would only play Trapmaker's Snare with the purpose of getting Archive Trap in a non-dedicated deck against Death's Shadow-decks and Burn, but I'm not sure the upgrade to a mill card you get in those cases is worth having a worse gravehard-hate in the sideboard slots meant for that kind of card. On the other hand, when also running many copies of Field of Ruin, Trapmaker's Snare is easily better than Breaking / Entering when you happen to also have a natural Archive Trap in hand - and they tend to rot there.. - and when you don't it is plainly a Startled Awake . It is also an important piece of many of your turn-4 wins: a new and common turn-4 win involves only a few cards (and certainly not the best ones!): 2 between Archive Trap and Trapmaker's Snare, 1 Fraying Sanity, 1 Field of Ruin and 1-2 other lands (depending on your Archive Trap/Trapmaker's Snare mix); and the mere chances of carrying it out makes Trapmaker's Snare so good that I would consider it over Breaking / Entering in any build including Fraying Sanity. Only beware of Leonin Arbiter and Aven Mindcensor.
Visions of Beyond: the first remark to note down is that Visions of Beyond does not fit as an aggro card (i.e. a component of an hyper-aggressive milling strategy, like one built aroud Fraying Sanity). It reliably draws into lands and mills spell when we need it, that is in the late game and especially when the game, for our opponent, is not about aggroing out; but even against aggro it proves useful, where it is mostly employed as a mean to dig into your library for fogs (spot removals are worthless in this case), which you can easily play on turn 4 even after Visions of Beyond. It fixes average hands and bad mulligans, seals good hands, and at worst it cycles with bad hands or in the early game (especially if in need of lands); as such, I consider Visions of Beyond as one of the core cards for a dedicated mill deck together with Hedron Crab and Glimpse the Unthinkable - the 'gear' of the deck, specifically. Note that Visions of Beyond is still great even when bringing in Leyline of the Void: if you don't start with the enchantment or they destroy it early, you get a powerful card; if Leyline of the Void sticks, you get to cycle it easily.
Snapcaster Mage: its presence in the deck is justified for the most part by its defensive capabilities; so let's break it down. As for inserting Snapcaster Mage in the deck because it being a creature is part of the value that the card can add to the deck, I must point out that that part of value is irrelevant in this type of deck: the reason is that there's a common issue with creatures in this deck-type, concerning the inability to block effectively when needed most (namely, against wide-aggro decks; or, for what it's worth, against decks that combine pressure and removals, letting them use their removal with no loss in tempo); least of all to attack. On the other hand, as for including Snapcaster Mage because the value it would add to the deck is letting us cast a good spell lategame - granted that the extra value makes worth having that good spell overcosted (which is often unaffordable for this deck) - then in general the trouble is worth if the deck can prolong the game consistently - namely, if the defence cards are good enough or in sufficient number (something typically not happening in Modern as a whole, and even less in Mill). So, if the versatility and the fact of being a creature do not accomplish much for themselves, it has to cover a proper role in the strategy - that is to say milling or defending: if more mill spell in the deck are needed, then play more of them instead of Snapcaster Mage; if affordable defence is needed, then it must flashback almost always a 1-mana defence spells - yet flashbacking a fog-effect is really not the place to be: 3 mana for that kind of effect entails losing the whole turn, making the spell pretty much useless (which is a different matter from what happens with a late Crypt Incursion). All in all, Snapcaster Mage is so inefficient (4 mana only to net average game-progressing value) that it makes fogs useless, hindering you in trying to win the game the following turn; and flashbacking a Visions of Beyond is very costly in terms of mana, as there is hardly a deck that allows you to make that investiment without punishing you. So, if you are on the fog plan, Mill gains nothing in playing Snapcaster Mage - whether under the 'creature' respect, or under the 'spell' respect (defensive, milling, or Visions of Beyond-esque); the high versatility of the card means nothing when none of its potential uses is effective for the deck's plan. On the other hand, Snapcaster Mage is very good with cheap removals and at getting both value and redundancy in general: for such reasons it is great against Jund. In the end, understanding when Snapcaster Mage is good is key: as a quick rule, Snapcaster Mage is strong when Fatal Push is good in any phase of the game; on the opposite, it is weak when Darkness is strong.
Driven by the milled-cards/CMC ratio and by the rule-of-thumb of trying not to end up empty-handed too quickly, it is easy to develop a nearly optimal 'straight-mill' list; the full optimization is not interesting, because it couldn't but very slightly change the outcome of the test. Interestingly enough, some lone testing permits to infer that the two extreme versions too of an aggro mill deck - both built to make full use of the number of cards and the mana available, but one exploiting the cards with the best milled cards/CMC ratio (demanding around 21 lands) and one trying to hit all of its land drops up to turn 5 without flooding (with about 24 lands) - tend to win on turn 5 when uncontested. However, a turn 5 win is patently too slow for Modern. This means that some sort of protection is needed in order to compete with the metagame. In addition, there are cards that against us entail a more or less automatic loss for us if unchecked: they will deserve special attention (unless you just hope to dogde them). Here's a list of the more problematic ones: Eidolon of the Great Revel, Thalia, Guardian of Thraben, Thorn of Amethyst, Laboratory Maniac, Platinum Angel, Gideon of the Trials, Leyline of Sanctity, Witchbane Orb, Aegis of the Gods, True Believer and other cards giving shroud or hexproof to the opponent, Wheel of Sun and Moon, Chalice of the Void, permanent land denial (like Leonin Arbiter, Aven Mindcensor, Blood Moon, Choke), Progenitus, Emrakul, the Aeons Torn, Gaea's Blessing Struggle / Survive Bow of Nylea Loaming Shaman Academy Ruins and other effects putting cards from the graveyard back into the library, and finally permanents that make your opponent skip her draw phase so as to let her simply wait for you to deck yourself (Maralen of the Mornsong, Colfenor's Plans, Dragon Appeasement, Molten Firebird, Null Profusion, Possessed Portal, Psychic Possession, Sundial of the Infinite!!). So, we must not only fend off their main strategy, but also concern ourselves with a way (at least with help from the sideboard) to deal with the locking permanents and shuffle-effects present in the metagame.
The cards in the deck can be thus roughly divided into two categories, according to the different roles played (in your ususal game at least: e.g. Hedron Crab is not counted for as an emergency blocker, because it is very very rare and unreliable to use that card this way): there are the ones milling, and the ones that keep the player alive or deal with lockers or shuffling effects - which I will call very comprehensively 'defence cards'. In the following part I will provide a list of the different types of defence cards available, as well as of the most effective (for our purposes) cards in Modern comprised in those categories. Our defensive needs are narrowed down further by the fact that we don't really need to be much controlling, or we would require some permanent mill engine like Search for Azcanta , Sphinx's Tutelage or Jace, Memory Adept: but building around them in order to make them worth would mean embrace the control strategy, and it would be unwise at that point to employ Glimpse the Unthinkable. You can just jump right over this part if you are acquainted with Modern defensive spells.
Set Adrift: it is the only clean and early answer in to Leyline of Sanctity, Ivory Mask, Witchbane Orb, Monastery Siege, Chalice of the Void, Blood Moon and other problematic permanents. We should try to play it in fullset before any other functional spell - i.e. before any bouncer - and even thinking of maindecking it if those pesky permanents are common in opponents' maindecks since they appear there in matchups that are usually good for us were it not for them.
Void Snare: unlike Echoing Truth it deals with only a single Leyline of Sanctity and it is mediocre even at that. Yet 2 mana is a critical cost for Mill because most of its cards cost 2 and need to be played early, so Void Snare can indeed fulfill the enchantment-removal role better than most other options. Because removing Leyline of Sanctity would be quite its only purpose, it seems bad: being a bouncer makes it significantly worse than Set Adrift, since the latter is an actual removal spell, which also comes in e.g. against Tarmogoyf: bouncers in general cannot really fill such role.
Kiora's Dismissal: Kiora's Dismissal, like Echoing Truth, can deal with multiple Leyline of Sanctitys, but it can also be a functional fog-effect against Aura when Leyline of Sanctity is dealt with. Unfortunately, those would be its only purposes.
Echoing Truth: for only 1 more mana than Void Snare, it can address multiple Leyline of Sanctitys; however, given the nature of the available mill cards, that single mana more is not worth an assurance against the risk of opposing more than one Leyline of Sanctitys.
Rite of Undoing: Rite of Undoing's potential synergy with Shriekhorn is really too slow - and when it would be relevant, the downside of Rite of Undoing being a bouncer backfires (i.e. they can easily cast Leyline of Sanctity).
Back to Nature: the best card against Aura.
Hide/Seek: if we can produce it surely save slots (being an answer to a single Emrakul, the Aeons Torn), but then the life loss from shocklands would become huge and casting the Boros part early would still be unreliable at least.
Paraselene: same as above; not being an instant and thus not being able to catch out the latest Auras is paid back with a bunch of life points.
Surgical Extraction: unfortunately, it is usually a win-more kind of card: against combo it is easy to sport a lot of incidental hate already, in form of cards this deck needs for other purposes. That is, it may happen that against random combo decks we are good enough with graveyard-hate, Set Adrift, spot-removals and fogs (the kinds of cards we should end up playing anyway), or just by milling them out. A timely play targeting an opponent's key-card could buy some time - if not winning the game on the spot against certain combo decks; but such combo decks are rare now aside from the ones which are already easy matchup for us or which represent other kinds of problems. Valakut and Tron are easy-wins (pretty much the only ones): (fast/reasonable) milling is enough, and we don't need Surgical Extraction at all; the same is true for Lantern and Ad Nauseam before they get Witchbane Orb or Leyline of Sanctity (and if you manage to get rid of them in a reasonable time, milling is often enough to win anyway). Vs Chord of Calling-decks removals (and Darkness against Elves) play a strong role, albeit there Surgical Extraction is a bit stronger against Vizier of Remedies. Dredge is already favourable with fogs, and we only get better with any graveyard hate. And vs Living End and Reanimator too we can bring in the hate we pack for Emrakul, the Aeons Torn, even though Surgical Extraction has got a little edge there. Against Jund-like decks Mill's strengh is redundancy in quality cards: having Surgical Extraction in the deck goes against it, all for a card that is useful only when you target Tarmogoyf in your opponent's graveyard AND your opponent doesn't have already one in play AND and your opponent can't kill you fast enough with other cards (or control the game with discards and removals). As an answer to Emrakul, the Aeons Torn, Surgical Extraction is actually the weakest graveyard-hate card: for instance, vs Through the Breach, once you conceivably use your whole hand to get rid of Emrakul, the Aeons Torn (that is, if you manage to dodge countespells which Surgical Extraction is exposed at, especially being the only spell they would ever need to counter) it is a losing proposition to race Snapcaster Mages and Lightning Bolts when you need to mill twice their deck. I argue for employing other kinds of graveyard hate - at least as long Emrakul, the Aeons Torn is not not played in 4x, and even then Leyline of the Void or Lost Legacy are still better than this. Additionally, Surgical Extraction is not to consider a cheap mill spell (at most it 'mills' 3 cards, even if mana-free), and extracting lands to power up any following Mind Funeral is not worth it (only 1 more card milled in average, which is very poor for a 2-card combination even if in marginal situations). As a side note regarding big events: Surgical Extraction makes some fringe decision intolerably hard: I am referring to the games where you are (or think you are going to be) at a disadvantage and you need to target any piece in their graveyard so that that action has the highest probability to slow down their play (i.e. hinder their contingent plan). This kind of situation comes up very frequently (especially if you choose to play Surgical Extraction maindeck, which I do not recommend - though obviously not for this reason!), and happens even against decks where Surgical Extraction is usually great (so that you actually sideboard it against them) because you could not see their key cards in the first few millings: the question is not to be taken lightly, and claims attention. The problem is that the choice is so difficult - being the alternative very close one to another in their consequences - that it demands you a lot of mental resources and more importantly TIME on the clock: expect your opponent to start complaining (not a real problem per se, actually), and more so after the very first time you do it against her. The stress involved is a matter to consider if taking Mill to a big tournament, and your opponent's complains do but make you wearier (which is the relevant part, as you can be enough self-trained or conscious of your actions to avoid other undesirable effects on your performance). So why should you ever play Surgical Extraction at all? Because in the end Mill is a very bad deck, and anything that can give us free wins (even if in extremely rare matchups only) is a welcome addition.
Extirpate: if you need graveyard hate not respondable to, but keeping 1 mana up for Extirpate regardless of the situation every time can be taxing so many times too many; this holds true even when you need to deal with Ancient Grudge in your Ensnaring Bridge build. And if you need your graveyard hate to dodge counterspells, something like Nihil Spellbomb is overall better.
Ravenous Trap: it is superior to the hate in form of permanent (Leyline of the Void, Rest in Peace, Tormod's Crypt, Nihil Spellbomb, Sentinel Totem, Relic of Progenitus) in that it is less disruptable (i.e. Boros Prison would often remove our piece via Nahiri, the Harbinger, Banishing Light or Wear / Tear before we ever mill Emrakul, the Aeons Torn; Living End has got Beast Within even in the maindeck..). In addition, the condition upon Ravenous Trap's alternative casting cost is quite easy to achieve, even in your opponent's turn: it is possible to do so by via Shriekhorn, Mesmeric Orb, Shelldock Isle casting any mill spell, Hedron Crab + a fetchland, even (not reliable but possible) Archive Trap. It is also possible that your opponent met the condition on its own, even during her turn, simply by playing her game (again, you should not rely on this, but it adds up). It is the cleanest way to deal with Emrakul, the Aeons Torn when it is played in a single copy (as it is in Boros Prison); in a pinch you could also plan to draw it with Visions of Beyond so as to cast Ravenous Trap with Emrakul, the Aeons Torn's shuffle trigger still on the stack. Also helpful against Dredge (even if not really necessary if playing fogs), while it is not so good against Living End: it is unlikely to meet the condition against them with a timing that is favourable for us. However, if you are more concerned with counterspells than with artifact-removals this card should be avoided in favor of something else. Finally, if the opponent is packing Ricochet Trap (and Living End does), Ravenous Trap can easily be worse than permanent hate. Remeber that you can search for them with Trapmaker's Snare, which is already a reasonable maindeck card if playing Field of Ruin.
Tormod's Crypt: good for diversifying the casting costs of your grave-hate against Chalice of the Void as we don't want to have all of our grave-hate costing 1 mana (they can deal with the first one, so we are likely to need to play another one after their Chalice of the Void on 1; and we probably need to save our Set Adrift for something like Leyline of Sanctity or Chalice of the Void itself).
Nihil Spellbomb: the drawing clause is the reason why this kind of card is to be preferred to e.g. Tormod's Crypt: thus we can be 'flooded' with this kind of effect without actually 'drowning' in them, alleviating any potential lacking of mill spells. It is better than the alternatives until Emrakul, the Aeons Torn is played alongside counterspells.
Leyline of the Void: unless playing multiple Emrakul, the Aeons Torns becomes the norm, or Storm and Living End are relevant matchups, its little artifact counterparts are better. Mind that many of your cards get worse with an online Leyline of the Void: Crypt Incursion, Surgical Extraction, Visions of Beyond, Fraying Sanity in my list. Overall, Mill cannot afford to play it: unlike any other deck, in many cases we don't need graveyard hate just in order to slow the opponents: we need it in order to start developing our plan! And should your opponent ever deal with your first graveyard hate card, you would be in bad shape with Leyline of the Void.
Yixlid Jailer: it is very hard to think of an Emrakul, the Aeons Torn-deck that cannot deal with a small creature even post-side, so that Yixlid Jailer is all in all more vulnerable than the likes of Nihil Spellbomb.
Lost Legacy: against Emrakul, the Aeons Torn, especially if played in multiples, and an answer against an in-deck Progenitus if there may ever be need; marginal utility against combo decks in general. However this kind of cards makes you spend the whole turn for casting them, when even a control deck can put up pressure in form of a clock or threatening a lock: be sure that in your plan casting it is game winning or that the opponent is usually too slow to punish you.
Bitter Ordeal: better than Lost Legacy if you need to take away different cards (like Lightning Storm and Laboratory Maniac against Ad Nauseam); but requires cracking multiple fetchlands. Not a good plan overall in any case.
Sadistic Sacrament: this is a 3-mana spell only virtually: it is difficult to have on turn 3; something like 4 or 5 mana is more indicative of the real cost - which is obviously prohibitive, and shifting to a more supportive mana base is not worth it given the alternatives. If in need of this effect against a single card, milling and then casting Surgical Extraction is all accounted for more reliable and faster.
Lazav, Dimir Mastermind: it is indeed a unique card, that theoretically can do a great job at solving one of our most frightening issue: combating Emrakul, the Aeons Torn-deck. However, once you manage to exile Emrakul, the Aeons Torn, those deck are quite easy to beat, so that there is not a great difference between games when Lazav, Dimir Mastermind becomes an Emrakul, the Aeons Torn and games when you exile Emrakul, the Aeons Torn early/inevitably. So the game, as usual in these cases, revolves around resolving your answer to Emrakul, the Aeons Torn, and unfortunately Lazav, Dimir Mastermind is very bad at allowing you to do that: against Through the Breach, at 4 mana it is very susceptible to counterspells (any other graveyard-hate at least cost less), and against Boros Prison its super-specific mana requirements make it impossible to cast it against Blood Moon - and it doesn't even do anything against their Leyline of Sanctity or other hate-pieces. Against Tarmogoyf-decks: Lazav, Dimir Mastermind would be a very late and difficult-to-cast and very-conditional blocker, and would achieve its utility-condition (milling a Tarmogoyf with Lazav, Dimir Mastermind in play) only when you would already be on the winning path (making it quite unnecessary); and it still dies to Liliana of the Veil, so that it could not block indefinitely: even when becoming a Tarmogoyf, it is a Tarmogoyf with a timer on its head. So Lazav, Dimir Mastermind unfortunately fits nowhere in any Mill strategy.
Grafdigger's Cage: not for fighting Emrakul, the Aeons Torn, yet a viable options as a strong bullet against specific decks such as Dredge or Company when a proper sideboard able to deal with anything fails.
Hide/Seek: it is good only against a single Emrakul, the Aeons Torn and it is not worth the splash (both Nihil Spellbomb and Lost Legacy do the same thing - which also happen to have a wider range of application).
Jace's Phantasm: the role of Jace's Phantasm is certainly NOT blocking against aggro NOR attacking vs combo, since they both are losing propositions: aggro decks go wide or are capable to deal with creatures with no tempo loss, while Jace's Phantasm into Jace's Phantasm into enabler (Archive Trap, Hedron Crab, Glimpse the Unthinkable, Mind Funeral) is so rare to get that you shouldn't count on it, and it is thereof a prospect that can be disregarded. Against control creatures are meaningless. Overall, Jace's Phantasm is only meant to be a blocker against midrange decks relying on smaller non-hatebears creatures, in that if they cannot ignore it you get a valuable defence card; however, Jace's Phantasm turns on their removals (Hedron Crab nets value before dying and must be answered immediately, so it doesn't count) and they will always have it: what they are engineered to fight is much more than 4 creatures a whole deck! Even post sideboarding they could not side out all of theirs removals because of nothing better to put in, so you should always take out Jace's Phantasm for your own removals. So, after all, it is bad even against midrange decks. Don't play it.
Wight of Precinct Six: it would be big only if your opponent plays many creatures, and in that case it would be useless both at defending your life total and attacking through that many blockers. This is a poor card.
Thing in the Ice : too slow in this strategy: our spells tend to be quite expensive, with many non-sorcery and non-instant spells.
Baral, Chief of Compliance: good vs Thalia, Guardian of Thraben when it also blocks well against decks that want her; otherwise, Baral, Chief of Compliance can't help us much since we mostly have only colored mana to pay.
Spellskite: if you have some free slots in your sideboard, this is meant to be an ace against any Infect-like deck; it is also good against Aura, so that you can keep a starting hand without enchantment-removals for Leyline of Sanctity if you see this because it buys a lot of time (if not winning the game by itself). However, Spellskite does nothing against Lantern or Ad Nauseam (which sport Leyline of Sanctity and/or Witchbane Orb), so that it couldn't fully complement your enchantment-removal suite. It has (hopefully) marginal utility against Burn. A shame that vs Infect and Burn, the decks it should hose, it is not so useful: too many removals in the first case (as I'll argue, we cannot afford to back it up), too little utility in the second one. In fact, Infect has plenty of ways to deal with it: Nature's Claim which Infect can even side-in regardless (not recommended though) because of our high artifact count (especially if we play Shriekhorn), and Dismember and Twisted Image which Infect could again side-in regardless (not recommended though) because of Hedron Crab and possible Spellskites.
Gifted Aetherborn: same as the previous, only a little harder to cast (maybe too difficult against Burn) and probably a (bad) side-in against decks like Jund.
Stinkweed Imp: useful against Infect if supported by removals.
Melira, Sylvok Outcast: if you desperately need to beat Infect.
Perimeter Captain: possibly with cards like Steel Wall, Wall of Omens and Wall of Shards. Walls in general are good if the field is only of little aggro decks with few creatures AND few removals (sure, it is a non-sense).
Meddling Mage: it would be useful vs combo or (even if marginally) vs Burn; but, unfortunately, it doesn't solve any of the common issues.
I am considering almost only 1-mana or less ones because if they cost more than that we will fall too much behind for being unable to cast our already no-impact mill spells (the most important and numerous ones cost 2+ mana).
Fatal Push: an important piece against Devoted Druid-combos, Hatebears, Jund, Burn and (even if less effectively due to their overload in protection spells) Infect. Fetchlands and Oboro, Palace in the Clouds are easy ways of bringing revolt about. It is also good as a tempo play, netting us hopefully a whole turn in which we could do our thing: in such case it is vital that it is cast in the very first turns - negating snowball-effects from early play; a nice feature that strives to add (even if just a little bit though) to the opposite scale pan (as to where such narrowness weighs) is that Fraying Sanity likes early plays gaining tempo and late plays milling (if the millers are not permanent, that is). As a removal, it actually plays out pretty bad with Mill's strongest option against aggressive decks (Darkness), but it is not hard to manage to sneak Fatal Push out early only for gain some tempo; that makes Fatal Push the best defence option available after Darkness (as a reminder of why, Surgical Extraction and Collective Brutality are too narrow, and both Ensnaring Bridge and Crypt Incursion need another defence spell acting as an enabler since they can keep you alive only from turn 5 on).
Disfigure: it is the best cheap instant removal in next to Fatal Push to answer quickly and neatly annoying cards like Thalia, Guardian of Thraben, Goblin Guide, Eidolon of the Great Revel, Leonin Arbiter, Tidehollow Sculler or Aven Mindcensor; therefore it should be played in fullset before any other functional spell (Fatal Push aside) if going down this route. Just keep in mind that (especially against Infect) Disfigure is utterly blanked by Mutagenic Growth, which is quite catastrophic.
Darkblast: vs Infect. At its best if you can diversify the answers (like in combination with Spellskite or Immortal Coil, better if both) so to have a shot at winning defending from multiple angles; but even alone sometimes it is gamebreaking enough for the Infect player. It can certainly do wonders with Immortal Coil against Infect, but it is bad against Burn where it cannot kill anything (at least spending only 1 mana, which is fundamental) or versus Hatebears (Thalia, Guardian of Thraben aside). It can be used in a pinch to fuel Set Adrift out.
Vampiric Link: mostly against Burn: enchanting their creatures to buffer the damage, or something like Jace's Phantasm to gain a ton of life; on their Eidolon of the Great Revel is hilarious; marginal use as a pseudo-removal against other decks.
Collective Brutality: great at catching up against fast creature combo decks (especially Infect and Burn) and small utility against hatebears and control. It's also a little help as an additional pseudo-gravehate against Living End (it discards Violent Outburst and Demonic Dread), Goryo's Vengeance-decks (it discards the namesake card) and Storm (it kills Goblin Electromancer and discards something) - even though you probably won't side it in in such matchups.
Sickening Shoal: if speed is of the utmost importance as against Infect; however, black spell usually are our best cards and we do not want to pitch them.
Path to Exile: despite it could seem the best removal for us, do not expect the opponent to search for the basic land (more below): she won't, or she will win anyway.
Engineered Explosives: typical answer to fast decks and especially to Aura, but against the latter you should already play enchantment removals for Leyline of Sanctity. Good when there are almost only permanents at 0- or 1-mana (even if you can produce more than 2 colors; in that case you are aiming at a single problematic permanent if you can cope with all the mana you are spending on it).
Drown in Sorrow: in a format full of Elves and Affinity perhaps it would complement our fog suite.
Damnation: classic mass-removal.
Yahenni's Expertise: it certainly seems strong when the first effect is good, negating the drawback of mass removals in Mill (being too much expensive in a deck incapable of supporting them makes them worse than a fog effect) in that you can play a spell alongside it.
Supreme Verdict: the to-go-card if in need of a white mass-removal or of an uncounterable one (sometimes it can be relevant, as against Merfolks).
With 'fogs' I mean functional copies of Fog. As nice as they play with Mesmeric Orb, we are interested in them as a tempo (mostly: mana) engine - meaning that you are looking for a way to cast other spells either in the very turn in which we cast our fog, or in the following turn(s) our fog can provide (that is, exceeding the one repaying for the turn spent in casting it). Such requirements rule out spells like Sudden Spoiling, Hydrolash, Gigadrowse, or Exhaustion.
Darkness: our main fog-effect. We plan to cast it on turn 4 at the earliest, since we cannot win with it otherwise. An average play of it buys you a turn for only 1 mana - and since it is difficult to cast all of our cards against aggro, it is effectively a Time Walk! Mind that Field of Ruin can shatter your plans of playing a spell alongside Darkness; though it is very well worth it given the importance of that land.
Crypt Incursion: secondary functional fog-effect. An average play of it prolongs the game of a couple of turns - and more in a fully developed game; but since 3 mana is a lot for this deck, casting it implies fully using the first of those acquired turns only to cast it: thus the comparison with Fog is even more fitting than it seems at a first glance. Being useful only from turn 5 on when we need it (a shortcut for doing the math involves taking into account the amount of damage decks like Merfolk or Sliver can output on turn 4 and 5), it does enough work quite only after playing another defence spell (Fatal Push on the first/second turn, or Darkness on turn 4): overall against aggro decks it is worse than Fatal Push, which instead of another card it only needs an appropriate temporal window - which translates into a condition much easier to satisfy. Another drawback is that Crypt Incursion would gain enough life to let you survive two more turns against aggro (so as to getting an actual turn in which you could cast your spells) only when Shelldock Isle would be ready to be activated; but at that point you could simply win the game. In a build with a lot of early milling it would be quite on par with Darkness, but such builds are too prone to lose to themselves due to incosistency (you cannot win without fogs at least because you need to draw more cards in order to actually win). Because it exiles cards, it produces an anti-synergy with Visions of Beyond: timing is very important, but it is easy to play around the impairment. Anyway, Crypt Incursion cannot be played in many copies because casting the second one achieves nothing - or it is irrelevant where you would need another mill spell instead - while drawing the first one, on the other hand, could be somewhat important. Added value is that Crypt Incursion gives you better plays against the sort of Dredge and Living End, which is a unique perk for a card that mostly wants to be mainboarded if played at all. Interestingly, however, getting an early Hedron Crab to survive or managing to cast an Archive Trap cast for 0 mana (that is, without help from Field of Ruin) are the most common ways of having turn-4 wins involving Crypt Incursion; but an early Hedron Crab or a free Archive Trap also happen to set up quite the only turn 4 Fraying Sanity wins (Crypt Incursion would be a bit worse in those scenarios since it doesn't win right away; still this is relevant only against very few decks). So why do I play Fraying Sanity over Crypt Incursion, or at least don't I consider playing both (perhaps as a split)? In fact, you don't want the fullset of Fraying Sanity because (1) you cannot cast the second one and at the same time 'win' on turn 4 (without a Darkness, that is), while if the second one were a Crypt Incursion you get a good chance to do it (mostly making an additional land drop so as to combine a 3-drop with a 2-drop, but also getting more value form Mesmeric Orb or getting to untap Shelldock Isle); (2) Crypt Incursion gives you better plays against Dredge and Living End - but still you don't want the full four copies of Crypt Incursion because the second one is useless, and (again) if the first one were a Fraying Sanity you could actually carry out one of those turn 4 'wins' without having to fog again on turn 5. The reason I prefer 4 copies of Fraying Sanity before any single one of Crypt Incursion is that (1) it is a very good mill spell, which is much needed to carry out good game-progressions; (2) we need a minimum of mill spells in the deck in order to limit the variance and being able to punish opponents happening to have bad gameplan-progressions; (3) Fraying Sanity is a stand-alone card because of the very deck composition (and one we can cast on curve to boot!) - meaning that we need an 'enabler' only to carry out turn-4 wins - while Crypt Incursion needs an enabler just not to be a dead card!! (4) you really cannot afford to play too many expensive spells: you already need to play many Mind Funerals at the very least, on pain of having both Crypt Incursion and Fraying Sanity return inconsistent results. In the end there is room for Crypt Incursion in the maindeck - meaning that Crypt Incursion is bound to be a sideboard card (if part of the deck at all). It would come in from the sideboard when it could play useful, as against Zoo which is very fast but keeps a low damage output throughout the game - though that is a more unique than rare feature among aggro decks. However, there is a chance that even against those decks your big mill spells in Fraying Sanity and Mind Funeral are too good to give up on, and you don't want to overload in expensive spells.
Immortal Coil: it is great both vs Burn and Infect: if you happen to have Mesmeric Orb too on the battlefield, they must remove it; and in a pinch, you can mill yourself with your cheap spells while pointing the big ones at the opponent. Unfortunately, sometimes they will have a removal for Immortal Coil (they could side in removals for your artifacts regardless). But it is still better than Spellskite (with a little help) because vs Burn Spellskite does too little, and of the reactive cards from Infect, only Nature's Claim is a matter of concern for Immortal Coil. A great choice against those decks if you have room in your sideboard.
Profane Memento: playing this card early against an aggro deck can gain around 20 life over the course of the game: it is outstandingly comparable to a fog-effect cast in the late-game; however, it is not useful if drawn later: it is totally comparable to a spot removal in such spots, so that we are left to see which has more added utility. Both Fatal Push and Profane Memento need you to play them very early, and they practically return the same result. The only difference is that Profane Memento is stronger when your opponent's damage output at a certain point becomes almost constant (like in Zoo, as opposed to Merfolk), but those circumstances are negligible since it is hard to come to a point where that matters even against those kinds of deck; on the other hand, Fatal Push is an all-star in particular situations, killing combo creatures (e.g. Vizier of Remedies) or hatebears (e.g. Thalia, Guardian of Thraben). So, Profane Memento is a fog in the best case scenario and useless otherwise: you'd better play Fatal Push over it, because exactly like Profane Memento it is a fog in the best case scenario and useless otherwise - yet it is your best defence card in some niche situations and matchups.
Send to Sleep: it is seemingly an impressive card in Mill. The trap is that it would be ideal to be able to safely casting it from turn 4 on (the moment we can reliably have spell mastery on) alongside a mill spell, but at that point spell mastery turns out to be useless (opposing creatures should not be likely to untap ever again: you should win at that point!) and at the same time it is meanignless to cast a double removal against an aggro deck (the kind of deck this type of spell is meant against) on turn 4 as they should be able to kill you anyway (or at least not giving you the opportunity to makes full use of your other turn, making you uncapable of redeem the mana you spent on Send to Sleep). On turn 3 it is higly unreliable, and even when you manage to cast it that early with spell mastery you get it at the price of not casting your copies of permanent mill spells like Mesmeric Orb or Fraying Sanity still in hand (as there could be a Hedron Crab or a Mesmeric Orb already on the battlefield, making a future Fraying Sanity much less effective, or you could't afford to not being able to cast many 3-drops in the future).
Fog: very good if the splash is worth.
These cards are meant to be brought in only against Burn (or quite so).
Sun Droplet: good together with blockers or removals, otherwise useless. Way better if played in multiple copies.
Chalice of the Void: since we have a hard time finding suitable 1-drops (see below) we can put them completely aside (apart from our blowout-cards: Hedron Crab and Visions of Beyond) and play this; however Chalice of the Void suffers pretty much from the same limits of Leyline of Sanctity against Burn, which is the deck it would be mostly meant against.
Leyline of Sanctity: vs Burn it is a real life-gainer - shielding you from burn spells. But it is unreliable, favors dead draws and must in any case be supported by removals: you would die from their creatures before you could mill them out; Eidolon of the Great Revel would still be unbeatable, and they can destroy your Leyline of Sanctity at some point with Destructive Revelry.
Authority of the Consuls: leaving aside infinite combos, Authority of the Consuls is good only against haste creatures; but at that point Disfigure or even Crypt Incursion are at least equally good (especially considering the stress on the manabase). It pairs well with Intruder Alarm and Mesmeric Orb.
Rest for the Weary: good if already playing , but their creatures would still be left to run around unchecked: it's but an expensive fog against Burn.
Timely Reinforcements: one of the best way to deal with Burn, with little application anywhere else; options need to be diversified for this to be useful (in order to lessen the risk of incurring into opponent's countermeasures): with removals and Crypt Incursion or Phyrexian Unlife, perhaps.
Ensnaring Bridge: [WARNING!!! The present entry only exposes the pros and cons of the card: for an analysis of the various Mill strategies employing Ensnaring Bridge, see below] This card is soft to incidental artifact/permanent hate (even maindeck, mainly because of Abrupt Decay, Maelstrom Pulse, Kolaghan's Command, Qasali Pridemage, Reclamation Sage, Engineered Explosives, Oblivion Stone, Karn Liberated, Beast Within...), and (much like with creatures, even if in a surely lesser, but still seizable extent) you cannot afford to lose that easily your only line of defence because it will most probably not be followed by additional defence - a problem in common with adopting spot removals as the main defence, as it is not trivial to cast more than 1 defensive spell in this deck without giving up to the ability to win consistently on top of the right one. Ensnaring Bridge is too fragile in that it is exposed to common and played-regardless removal spells: hate is to be expected as heavy played especially after sideboard, when the opponent brings in a lot of marginally useful or even probably dead cards (graveyard hate, artifact- or enchantment-removal..) because they have a bunch of surely dead cards maindeck against us; Ancient Grudge is the most frequent of the brought-in, and it can even be cast from graveyard after we mill it (sure, if they get Ensnaring Bridge they won't destroy your Mesmeric Orb.. but to what end, if you cannot live long enough?). Mill is a frail deck: if only 1 of your spell is thwarted (even a milling one, but there is no point in that since it is enough for them answering the defensive one), you lose any chance to race out racing decks (i.e. quite any Modern deck); this is especially true about Ensnaring Bridge since it costs too much and comes in too late to take you ahead in tempo when thwarted. However, that is less of an issue when we compare an Ensnaring Bridge list to any other build: between Mesmeric Orb and Fraying Sanity permanents makes up for a big part of our milling engine, meaning that a removal on any of them would take out our ability to win in the time our defensive means would net us. Another concern is that Ensnaring Bridge works poorly with other cards: it requires playing suboptimal cards (blockers, removals, Collective Brutality, Surgical Extraction to get rid of what can deal with it, and perhaps even millers like Shriekhorn or Breaking / Entering that are less efficient than what you would play in order to win without it, i.e. not enough to win most of the times without an Ensnaring Bridge!!) and adopting suboptimal lines of play (casting spells in an untimely manner, like a Surgical Extraction on an irrelevant target or a Visions of Beyond for drawing but one) to be effective, such that leave you in no position to win the game without giving the opponent a lot of time to deal with the lock. It bickers with Archive Trap which can remain unused in hand; or with untimely/unlucky Visions of Beyond (even if cast in your opponent's end phase) or with land-heavy/-light draw (lands or cards respectively will remain stuck in hand). And more than one of such events can happen simultaneously, making the card look silly more often than not (finalized and fine-grained deck-building and tight play can do very little about that - as we will see). Not being a catch-all answer to creatures in a meaningful way can be easy exploited by opponents, as 0-force creatures like Noble Hierarch and little creatures in general (from Infect, Affinity.. which can buff their creatures after having attacked, or even move Cranial Plating at instant speed) can attack regardless: I understand that a Noble Hierarch will take and eternity to kill, but when Ensnaring Bridge is cast or is fully operational (mostly turn 5, turn 4 at the earlier) we will have already taken a lot of damage; we would want to try and not to reckon on the potential support a timely Crypt Incursion could grant: any list even at least dreaming to be viable could boast a quite safe victory with a resolution of that spell at that point of the game. I see an argument for Ensnaring Bridge against reanimator, but a fog against Griselbrand is mostly equally effective (and at 3 mana you could also have Crypt Incursion - though you should be dead in any case on turn 3, i.e. you should not be able to cast Ensnaring Bridge anyway) and preventing Emrakul, the Aeons Torn from attacking still leaves open the question of how we win: most ways to cheat it into play see to it that it doesn't stay on the battlefield for long. Changing viewpoint, Ensnaring Bridge makes our mulligans way stronger - which is actually a very strong point. At worst, you could even plan to mulligan with the sole end of getting Ensnaring Bridge online sooner. Surely, albeit being useful only from turn 5 on like Crypt Incursion (see below), it is stronger against discards (it is better as a single card, and it isn't nullified if they take your mill spell); unfortunately, decks playing discards are the more capable of dealing with it: Abrupt Decay, Maelstrom Pulse, Kolaghan's Command, Liliana of the Veil, Cryptic Command only to name their more common maindeck resources - so that this invalidates the whole argument about Ensnating Bridge being stronger against discards.
Intruder Alarm: it is good only if the opponent plays very few creatures, and very risky in any case.
Silent Arbiter: if your opponent has no creature removal and it can block any of your opponent's creature without dying, it is better that Ensnaring Bridge because it absorbs all damage from a whole turn earlier.
Noxious Revival: it can be useful to re-draw a much needed spell like Darkness, Ensnaring Bridge, Glimpse the Unthinkable or a fetchland depending on the situation; under this respect, it is an alternative to Snapcaster Mage that costs no mana - even if the card is acquired later, it costs life and it provides card disadvantage (which, anyway, can be a boon if you are playing Ensnaring Bridge). Noxious Revival in rare occasions can also cover the disruption role against cards like Snapcaster Mage, Unburial Rites, Eternal Witness, Murderous Redcap, making it quite a deep card. Where it truly shines, however, is in providing the much needed depth in the enchantment-removal department: Set Adrift is pretty much the only available answer to Leyline of Sanctity, and Noxious Revival can be its copies 5-8 (we would be milling ourselves anyway against Leyline of Sanctity beacuse of an early Hedron Crab, Mesmeric Orb or simply in order to exploit Visions of Beyond or Shelldock Isle).
Claim / Fame: it mainly reanimates Hedron Crab; but non-interactive decks don't kill our Hedron Crabs (though we can mill Hedron Crabs with Mesmeric Orb) and interactives ones have got more removals than we have got Hedron Crabs+Claim / Fames so that it is hardly of any help. In the sidelines, it brings back Snapcaster Mage, Jace's Phantasm, Minister of Inquiries or Manic Scribe if your plan needs them.
Search for Azcanta : especially with Mesmeric Orb, this is indeed a Rampant Growth for Mill, which makes it very interesting and unique. However, as you can imagine the 2-mana slots are pretty much stuffed, and in Mill there isn't very much to ramp into (see the section about mana creatures). The activated ability is pretty much useless because if you get the chance to activate it either you are playing a controlling version - and you should totally do without mill spells altogether at that point - or you are against control, which is already a very favorable matchup for mill.
Serum Powder: it would be used to maximize the chances to see at least one enchantment-removal or a graveyard-hate post board: we really need to have them in hand at the beginning of the game. However, it is probably better to split its slots into proper answers - even if doing so lowers the chances to see them compared to them together with Serum Powder - in order to have more impactful options at every stage of the game (especially if the first ones are dealt with).
Pyromancer Ascension: unfortunately, there aren't cheap or good ways (less both) to abuse Pyromancer Ascension in Mill; apart from dream-like draws, it would be slow, inconsistent and without Pyromancer Ascension it would do nothing (even if you could refill your cheap mill spells with Visions of Beyond).
For completeness, let's also take a look at what lands we could play. I will consider only palatable cards for a build; potential splashing is to be appropriately integrated.
Island: be sure to sport the bare minimum to search safely (i.e. without much splash damage) while also leaving one in the deck for your late Field of Ruin activation. The only caveat is not to play too many only- mana-producing lands (you'll already want a full playset of Shelldock Isle).
Swamp: sometimes we need to cast Glimpse the Unthinkable+Darkness early, so mana is somewhat important - though do not play too many only- mana-producing lands (given the heavy blue-mana demands of the deck and the fact that we'll want as many Field of Ruin as possible); in particular, a starting hand without at least one non- mana-producing lands is a sure mulligan, and we want to keep that possibility at a minimum. It also works towards Mill's risilience to Blood Moo.
Watery Grave: they open up a lot your possibilities of your fetchlands and of your strategy as a whole; be sure to play enough to have sufficient lands against control and have an insurance in case Mesmeric Orb mills your fetch targets.
Polluted Delta: you don't want to play games where you have an early Hedron Crab and don't follow it up with enough fetches in the course of the game. Still, it is hard to balance the need to exploiting your best card and most reliable fast win, the need of sporting enough real lands and the need of not taking to many damages from your own cards. They are also excellent at getting revolt for Fatal Push.
Flooded Strand/Misty Rainforest/Scalding Tarn: one could choose to play -fetchlands after Polluted Delta so as to bluff the splash; but also the split between Flooded Strand, Scalding Tarn and Misty Rainforest is reasonable in order to avoid potential and untimely (for us) Surgical Extraction- or Pithing Needle-effects. The last one actively comes up against Lantern, since they will deal with your Shelldock Isles by means of their Ghost Quarters and will try to name your fetchlands with Pithing Needle: while we cannot prevent them to make our Polluted Deltas miserable, we can make their second copy of Pithing Needle useless exerting splits in our fetch-department. Now that the -splash for Path to Exile is not credible - since not only Path to Exile is bad in Mill but also made obsolete by Field of Ruin (actually forcing them to search, and a land to boot) - and bluffing sideboard cards seems too much a stretch, you should go for the split.
Shelldock Isle: if considering this an aggro deck (i.e. attacking via independent spells until winning, not really caring about reacting if not for staying alive..: it could be indeed a more fitting description than it looks), this is our Mutavault: it gives mana in the early-game and cast a spell in the late-game - which depending on the situation could be a big mill spell (hopefully Archive Trap), the preferred and most frequent choice by lenght, a fog-effect (which is equally good against aggro) or a Visions of Beyond which, even if it is usually worse than a mill spell, sometimes is still a worth play even at that mana cost (especially against attrition-based decks). Such feats make it really impressive, despite entering tapped and the sometimes taxing strict color requirements (, all things considered): plan ahead and fetch accordingly! All in all, Shelldock Isle is a real deal: it is a land with your best spell attached. Sure, it is worse than another land under the land respect (since it enters tapped), and worse than another spell under the spell respect (since it needs to meet certain conditions in order to be cast). Nonetheless, every part of the effect of the card is still useful, and getting to have both along the course of the same game is huge - which is something not even Snapcaster Mage can grant. For better contextualisation, you can compare this with my thoughts about Snapcaster Mage: Snapcaster Mage could do wonderful things for this deck, possibly being a mill spell or a defence card (you get only one of them though, if it is a consideration: in this deck the body will hardly scrape together a relevant block - that is s block in a way that gives you tempo - so it does not count as a part of the defence Snapcaster Mage can grant); yet Snapcaster Mage overprices your choice in a way that could be unaffordable for this deck: at least 3 mana for fogging (not really gaining an extra turn because of mana inefficency) or 4 mana for milling. With Shelldock Isle not only you get both its effects: they are very affordable too! And it circumvents the impact of any opposing Choke. In the end, Shelldock Isle despite entering tapped is astonishingly good: in order to win this deck needs to cast around 5 big mill spells - such as Glimpse the Unthinkable, Mind Funeral, Fraying Sanity, Archive Trap, an early Mesmeric Orb possibly with fog coverage, an early Hedron Crab which survived late. Shelldock Isle entering tapped tally with the poverty in useful 1 mana early spells, and overall if you play enough lands you can easily find a spot in the curve to play Shelldock Isle without delaying key spells. Despite its harsh conditions of activation, Shelldock Isle is not a win more: with 20 cards left in the library you would need a couple of mill spells anyway. It actually grants you a sort of card advantage and it is an important piece of the mill department; and if you count Shelldock Isle as a spell, its cost in mana partly repays itself over time (when you wouldn't have played another land anyway) because on the turns when it isn't casting the exiled spell it's a land giving mana! It is the perfect card for the fog plan, allowing you to fog on turn 4 and cast two mill spells on turn 5 for the win (it comes up quite a lot!!!). In conclusion, since Shelldock Isle is a really strong card and essential as to hit the critical mass of mill spells (5) in a reasonable time (turn 5), it would be a sorely mistake not to play 4 of it here.
Oboro, Palace in the Clouds: it is wonderful with Hedron Crab when not drawing lands, and can give double when needed (if not playing other lands). It is of no use in decks with so many lands that they are guaranteed to make all of their land drops till late in game. Excellent at getting revolt for Fatal Push. Like most of the following cards it is good against Choke and if you have too many fetchlands in the deck - since you could find yourself fetching in the very first turn, which is not ideal because later fetches have less targets (and permit fewer choices) and because fetches are meant to feed Hedron Crabs.
Sunken Ruins: the same consideration made for River of Tears applys here, with the relevant extra of fixing colors (1) from Island/Shelldock Isle for an early Glimpse the Unthinkable/Breaking / Entering/Mind Funeral + Darkness, or (2) from Swamp in order to activate Shelldock Isle (colored mana is highly stressed even lategame). This is of great help when you naturally draw the wrong lands or if you need to fetch for basics more than you would in order to be conservative with your life points. It actually saves more than a single life point over the course of a typical game.
Darkslick Shores: very strong in the early game, I suggest not play more than 1 because the second copy is ugly (you want fetches early in any case for Hedron Crabs). You should play it if you are not playing Crypt Incursion, Darkness or Fraying Sanity since in such cases we want to make full use of our mana from turn 1 to turn 5; and we should already feature Shelldock Isle as a surely tapped land on later turns.
Port Town: no Mill deck can play that many basics: it will always come into play tapped.
Fetid Pools: the drawing part is pretty much irrelevant since you will happen to manage to cycle at 2 mana only in half of the games (the slow ones) you play against grindy decks - and never anywhere else.
Waterveil Cavern: good if we are not playing Crypt Incursion, Darkness or Fraying Sanity (in such case we want to make full use of our mana from turn 1 to turn 5) and we do not go much deep as to colored mana requirements (like if we play Shriekhorn instead of Breaking / Entering).
Nephalia Drownyard: it is not against slow decks that we could use a hand.
Ipnu Rivulet: same as above for a one-shot use in exchange of producing blue painful mana (which makes it better than Nephalia Drownyard). In other words, we would get to activate it only against those rare slow control decks, against which we have already the edge: an additional double land (perhaps a fetch?) as an insurance against color-screw, a basic land more against random Blood Moons or more simply another painless land are in any other case more valuable than Ipnu Rivulet. Ipnu Rivulet on the other hand boasts a similar activation cost of Shelldock Isle, but even when you activate it milling only 4 cards is irrelevant: Mill bites out the opponent's library by chunks of 10, for a total of 50: there's no need to spend resources to round up the mill count if you can avoid it, and while there are some arguments to do that in the early game by means of little mill spells, there are none for the late game. There are certainly builds that don't want Shelldock Isle where Ipnu Rivulet could shine, like a dedicated Fraying Sanity build, but I don't think they are good enough.
Ghost Quarter: if mana permits (almost all of our cards need only colored mana to be cast), it can be used as part of a color/land-denial tactical ingredient (more below). Remember this is not a way to cheat your Archive Traps because searching is not mandatory, and your opponent won't search if not for winning regardless of your plays.
Field of Ruin: as opposed to Ghost Quarter and Path to Exile, THIS is a way to cast your Archive Traps for their alternative cost: your opponent is actually forced to search! The tricky part is that you hardly get a discount for your Archive Trap if your deck is too much color-hungry, as you'd really want your first 4 lands to be colored ones; in that case, you'd get to cast Archive Trap for 2+1-1=2 mana IN THE TURN YOU CRACK Field of Ruin (saving you 3 whole mana in that turn), yet in the former turns Field of Ruin will hardly help you casting anything - making your efforts way less appealing: so do not go deep in spells like Breaking / Entering. This is especially important because it makes harder casting a spell alongside Darkness, missing the whole point of fogging off in case you don't meet the color requirements. Actually, it would hardly be worth the strain on your manabase - even when including Trapmaker's Snare or Manic Scribe into the plan because of their friendlier mana costs - if not for the fact that, even if you do not get a proper discount on you FIRST Archive Trap, you still get huge ones on any other copy of Archive Trap in your hand! Also, Field of Ruin opens up to a lot more turn-4 wins (foremostly with Fraying Sanity), and that alone overall makes it worth to play this combo. Finally, it allows you to count Archive Trap, in some way, among the mill spells you can play on curve - as opposed to when you could cast Archive Trap pretty much only as a consequence of your opponent's actions: this is valuable because it frees some slots in favor of the defensive spells department. Note that it is useful against Blood Moon, Choke and for getting rid of Academy Ruins.
Academy Ruins: great tech: late game it retrives mill spells (Shriekhorn, Mesmeric Orb), defence cards (Ensnaring Bridge, Engineered Explosives..) or grave-hate (Nihil Spellbomb, Relic of Progenitus, Tormod's Crypt..); and it can recoup those items because you already used them once/they have been destroyed, because you auto-milled them with Mesmeric Orb or because you milled them with other spells (e.g. you are milling yourself as a part of an alternative plan..). All that makes Academy Ruins a very versatile card. However, playing a colorless mana source in a deck with so few lands and too many very specific color-requirements (nearly every single spell, and Shelldock Isles..) makes for very awkward sequences on your part: the games in which you draw it without planning to use its unique ability (and you will use it but very very rarely) see you in too bad a spot. It is thus sideboard material; but at that point you probably want an additional grave-hate (since it will be the most frequently recurred kind of card).
Gemstone Caverns: it could be sideboard material, allowing you to catch-up on mana when the opponent starts if you see it in your starting hand, and if you can afford to have a quite sure dead draw in the course of the game (colorless mana ends up being pretty useless, especially in the list highlighted here). All of these conditions are met if you have to draw first against aggro or combo; but that makes Gemstone Caverns nothing more than a narrow and unreliable sideboard card: against anything else a dead card is more liable to exert influence upon a game than a totally unreliable way to get ahead on tempo. Pondering alternatives routes, adopting Gemstone Caverns in the main plan can only be detrimental: since you will always want to play second, the card is of any use if you need to draw a very specific card along the course of the whole game (and not only in you first hand: if it is so, it is better to mulligan than hoping to draw it otherwise), and if neither you (without that card) nor your opponent put any pressure: only this way drawing first is of any utility, i.e. when 'drawing first' means 'drawing extra' (because the card drawn is the only one relevant, and after that you close the game). Said that, aside from some combo mirror or a dedicated strategy I cannot see any profitable use of Gemstone Caverns - and much less in Mill.
Scavenger Grounds: it is already hard keeping mana up for Relic of Progenitus or Extirpate, so it would not be the main answer to Emrakul, the Aeons Torn. And, as for lands, we have more pressing priorities.
Now I will showcase some popular or peculiar plans I found bad, including build-arounds demanding a little more than a shallow analysis, and exhibit reasons for my judgement. Again, If you are not interested in learning more about any particular plan not worth to be executed, you can just overlook this part.
It may well glare out that Fraying Sanity combos out with Traumatize, though such a deck would be but a worse Ad Nauseam and in any case Glimpse the Unthinkable would be unneded there; on the other hand, in a build wanting Glimpse the Unthinkable, Traumatize (and 5-drops in general) would be largely unneeded in order to win on turn 5: you can already win with the cheaper cards you need to play in any case (on pain of needing a combo, a mill engine, a draw engine or defence cards greatly effective against anybody), and worst come to worst Archive Trap would achieve the same result as Traumatize with the perk of being more all-around. So, a Traumatize+Fraying Sanity build could sport more defence than a Glimpse the Unthinkable deck (since it provides a combo finish), but it couldn't play Glimpse the Unthinkable without wasting slots (and that's what I am actively trying to avoid).
One could be tempted into going full-combo with Field of Ruin. You have a lot of feasible tutors for Archive Trap in Trapmaker's Snare, Merchant Scroll and even Infernal Tutor. Merchant Scroll could also get Visions of Beyond against attrition decks; but the most interesting one is certainly Trapmaker's Snare, which in sideboard games could get you other traps like Ravenous Trap. In order to get Field of Ruin we could sport Expedition Map, Tolaria West or even Sylvan Scrying; they could also search for Shelldock Isle against grindy decks in case. Unfortunately, if you don't draw your Fraying Sanity it gets almost impossible to win before turn 5 - while adding interaction could very well confict with your needs in synergy. To boot, with all the tutors and so little action you'd become more vulnerable to cards like Thoughtseize, Surgical Extraction and Blood Moon than it is necessary.
Unfortunately, Fraying Sanity falls only a tiny bit too short for being playable on its own, meaning that a 'turbo-mill' built around it is not the way to go. A Mill build with Darkness or Crypt Incursion can fog its way to the win from turn 4 more often than any dedicated Fraying Sanity build can win on turn 4. Just consider the ways to achieve a turn 4 win as to a Fraying Sanity built-around and my very list respectively: almost all of those additional turn-4 wins Fraying Sanity could purport involve resolving 2-3 one-mana mill spells in the first two turns of the game or a turn 1 Birds of Paradise with a full curve - which makes those wins very very rare and can overall be disregarded. On the other side, fogging is relevant (i.e. better than simply stumbling/having a consistent win on the following turn based on the deck's composition alone) since many decks wins through combat. Adding fogs to a Fraying Sanity-centered strategy given the present quality of mill cards is surely detrimental and should be done with caution, since Fraying Sanity is a combo card of the kind which demands a wide range of options as to what to play next (because even among the mill cards some end up being narrow) in order to give a significant performance: if you play too many fogs you end up with too few mill spells and take out further consistency to your Fraying Sanity wins; if you play too few you are giving up on too many early fog wins, which come up much more often and are almost equivalent. The mill cards available as to now don't permit to assemble enough turn 4 wins for a Fraying Sanity all-in strategy to be consistent (namely, if we make Fraying Sanity wins consistent we cannot manage to win without it at an acceptable rate); under this respect, building aroud Fraying Sanity is like building around Ensnaring Bridge: you can't really win if you don't draw the namesake card and have it stick around until you're done.
This strategy aims at removing lands from your opponent's deck in order to get big Mind Funeral; for redundance, you can have Snapcaster Mage and Mind Grind at worst. However, this plan has loads of flaws. You hardly want Path to Exile: removal spells are bad if they are not supported by other defensive plays of a fast win, and this deck can do neither; and even exiling a creature for one mana with no downside (i.e. your opponent not searching for the land) is not useful here by any means: this deck do not care about card/value advantage (if here value does not mean to break out combos or gaining tempo). Ghost Quarter is of any use only in the early stages of the game (i.e. usually not further than turn 2) because the relevant threaths can easily come down with the amount of mana available at that point, and we want the opponent to search; but then you are behind in the game by a land drop and a card just to be able to cast a card in your hand (Archive Trap) that is not even that good: if you activate Ghost Quarter on turn 2 and the game lasts, say, 5 turns, casting Archive Trap costs you 4 mana in the end! It's functionally like a Startled Awake that requires a combination of 2 (otherwise dead) cards in order to be cast (even if you would already play Archive Trap regardless of the synergy) - and if the opponent doesn't search, Archive Trap could just sit in your hand for the rest of the game! I am aware that being card-conservative is not an integral part of this strategy, so it would not be a big deal to have a built-in two-cards mini-combo; but this particular plan implies an unnecessary squander of resources for a really mediocre achievement. Sure, sometimes this plan can strip the opponent of some of her resources (even from her hand, especially with a lucky Surgical Extraction pointed at a non-basic land played in many copies); but lands played in a relevant amount of copies by aggressive decks especially (and in Modern in general) are very rare apart from fetchlands, which we sometimes don't want to extract in order to have a better chance at casting a late Archive Trap (as I argued, they should often refuse to search because of cards - ours or theirs - different from (early) fetchlands). Anyway, it is quite impossible to actually get the opponent screwed on colors or total mana if they don't have the targeted land in hand - which is very rare and we should not rely on that: we shouldn't play Surgical Extraction with such objective in mind (even if we can time its casting so as to have a greater chance to accomplish that, i.e. her draw phase). And if you plan on casting Surgical Extraction on lands in order to power up a following Mind Funeral, don't do it: the computings below (see Mind Funeral's entry) show that 3 lands exiled from the deck allows Mind Funeral to mill averagely only 1 more card than normal. Also, there are manabase considerations: playing a (possibly high) number of Ghost Quarters and Field of Ruins plus being able to cast Path to Exile on turn 1 if needed, in addition to strict color requirements imposed by other spells makes the manabase very strained: it implies a high count of fetchlands and mostly untapped shocklands, rarely having room for listing even a single Plains. These numbers entail huge life loss over the couse of the game, which pairs up poorly with Path to Exile as a defence card. Ghost Quarter and Plains would be more affordable if also playing Shriekhorn and Mesmeric Orb; but there is no room for them in such a build because of the high dedication the deck demands for each sub-plan in order for them to be of any use. Moreover, the overall resilience of this strategy is extremely low: each card per se doesn't do much; especially considering that Ghost Quarter, Path to Exile and Surgical Extraction wouldn't have taken you any further in regards of your own plan, and they do nearly nothing against most opponents. Even if everything goes as wanted - which is something not granted at all, given the choices offered to the opponent and the incongruence with other objectives (i.e. casting spells and staying alive) - even if you succeeded in ghosting, extracting, pathing someting and then trapping/funeraling, you end up without cards and nothing accomplished (Visions of Beyond or Shelldock Isle would hardly be ready at that point!), and you will get crushed even by an opposing Snapcaster Mage cast on turn 2; and if they counter or discard your Mind Funeral, you will end up without anything meaningful in hand anyway, adding the resilience problem to the structural inconsistency. Finally, this strategy is slower than it seems: it leaves more open to things going wrong (i.e. flooding, losing to combo or to a single undealt creature...).
There is a build worth calling 'Suicide Mill', which main game-plan featured Street Wraith, Mishra's Bauble and even a splash for Manamorphose. The strategy is a bit unreliable yet capable of very fast wins (turn 4, which is very good for Mill) - but, needless to say, it got smashed by any random creature because of the huge life loss (mentioned cards + a lot of fetch-/shocklands inevitably untapped because of the speed requirements and the low land count needed by this this strategy). Throwing in Death's Shadow would but make early wins more inconsistent.
There are a lot of permanents capable of chipping your opponent's library away - the most interesting ones being Altar of the Brood and Grinding Station. However, despite existing an appealing alternative win-con involving Altar of the Brood, Heartless Summoning and multiple Myr Retriever (at least as a sideboard plan), strategies involving those cards require you to play so many suboptimal cards that it is literally impossible to carry out a win (the lack in quality really adds up).
We could easily have some artifact for the first activation of Thopter Foundry even if we don't have a Sword of the Meek: those two in addition to Shriekhorn and Mesmeric Orb already amount to 16! We can as well mill ourselves until we get Sword of the Meek into the graveyard if we already have Thopter Foundry in play (Mesmeric Orb even does that naturally!). This plan is a very neat and easy addition to the whole strategy. Sadly, it does not solve any of Mill's problems: it is too slow against aggro if not supported by removals; it works against the redundancy requirement against midrange; and it doesn't do anything against shuffling effects and problematic permanents.
You can try to attack with creatures in games 2-3 where the main plan is undermined (namely against Emrakul, the Aeons Torn or Leyline of Sanctity): this should dodge usual hate against a spell-based combo deck as Mill is. A starting point might feature this sideboard: 2 Tasigur, the Golden Fang, 4 Gurmag Angler, 4 Sibsig Muckdraggers, 4 Shambling Attendants(/Tarmogoyf if -splashed), 1 Laboratory Maniac. The plan would be to mill ourself and cast those huge creatures. Because against Leyline of Sanctity we cannot mill the opponent (Mesmeric Orb would be too slow), and against Emrakul, the Aeons Torn it would very risky (and those are the cases in which this plan would be needed most), it is no use playing Jace's Phantasm or Wight of Precinct Six. Laboratory Maniac allows for an alternative win - which, even if very hazardous, it is a welcome out when the game would be otherwise unwinnable; if it is accidentaly milled out, it can even be recurred by Sibsig Muckdraggers. The problem is that this plan is too slow: Ad Nausem can win long before letal damage, and Aura can set up a gigantic lifelink creature we could never overcome, and it also has Path to Exile for our Laboratory Maniac (even if we can win at instant speed via Visions of Beyond). Shouldn't this be enough, Burn and Infect remain unwinnable match-ups. As for Death's Shadow, fetchlands alone are not sufficient to put it online.
Sideboarding 4 Prized Amalgam + 4 Bloodghast + 4 Haunted Dead + 3 Stitchwing Skaab (I think they would be much better than Narcomoeba here, though getting to the right solution would change very little): we mill ourselves, activate Haunted Dead which at the same time puts possible creatures from hand into the graveyard, and attack until we win. Unfortunately, this plan has an average turn 5/6 kill, too slow against anybody. And against Aura we still cannot win mainly because of lifelink. I've seen adopting this as a maindeck plan for Mill, relying on a sideboard of only mill spells to beat the maindeck-plan hosers; still, it is too slow to win and therefore a bad idea.
Otherwise, an option is featuring an 'Unburial Rites-package', with Iona, Shield of Emeria and the like: milling ourself, we can cast Unburial Rites quite reliably on turn 4. The problem is that this plan is an 'all-in' and very fragile one; also, we cannot choose which reanimation-targets go into the graveyard, unlike than via Gifts Ungiven: the wrong one will be most likely unsufficient to win (and sometimes even the 'right' one). And it is too slow most of the times. Including Gifts Ungiven would make us win on turn 5 at the earliest, which is too late in a deck without interaction.
A last attemptive down this road might see roughly the following 15 cards: 4 Laboratory Maniac, 4 Noxious Revival (and/or Unburial Rites if willing to splash ), 4 Dispel, 3 Swan Song. Mill yourself, make sure to draw a Laboratory Maniac (via Noxious Revival if necessary) and cast it protected with counterspells. Unfortunately, this plan is very very slow - too much to compete. Lantern, Ad Nauseam, Storm, Aura, Boros Prison are the typical decks playing Leyline of Sanctity in the 75 right now. Boros Prison, Jeskai Nahiri, Blue Moon, Goryo's Vengeance, Krak-Clan Ironworks on the other hand are the decks sporting at least an Emrakul, the Aeons Torn. It seems that each and every of them can win faster than us or disrupt our Unburial Rites + Laboratory Maniac combo: Lantern has got Abrupt Decay and Surgical Extraction; Ad Nauseam, Storm, Aura, Krak-Clan Ironworks and Goryo's Vengeance represent fast wins (even with fewer cards than normal due to mullingans into Leyline of Sanctity); Storm, Goryo's Vengeance and Boros Prison have got Blood Moon, to which Boros Prison adds Chalice of the Void and perhaps even a Boil; finally Jeskai Nahiri and Blue Moon are full of counterspells. All this sometimes accompanied by reactive cards from time to time incidentally good against us: creature/artifact/permament removals, meaning that we cannot rely on that Hedron Crab or Mesmeric Orb not even post side, and more importantly if they happen to side them all out they would put them back the following game in order to kill Laboratory Maniac - so that we couldn't adopt the same plan twice against them, which is a serious problem since we wouldn't have another plan in the matchup. We should shun a transformational sideboard that can never win.
We could sideboard 4 Madcap Experiment, a couple of Platinum Emperion and a Steam Vents (making sure all of our fetchlands could get it). But Platinum Emperion doesn't really help against Leyline of Sanctity and Emrakul, the Aeons Torn (it is unlike those kind of decks do not have a removal, even if post side and against us); and Burn can win on the fourth turn, and in the worst case they can draw a removal any time (they could bring in artifact removals regardless). In the end, albeit it offers another angle of attack and it is quite fast, this plan is extremely brittle and doesn't really solve our issues.
If you need to play this combo, Duskmantle Guildmage could be a standalone card worth to be in the maindeck (perhaps to free up sideboard slots), if it wasn't too much expensive and frail when it isn't needed to make up for the times when it is: when it isn't a blank card, against anything apart from an Emrakul, the Aeons Torn or a Leyline of Sanctity deck you would win with anything else earlier and with much less mana. As for Duskmantle Guildmage + Mindcrank being a mere sideboard plan, there is hardly an Emrakul, the Aeons Torn or a Leyline of Sanctity deck that couldn't deal with such a fragile combo (Duskmantle Guildmage is a little creature at the very least!); and even if it weren't the case, finding 1 out of 4 graveyard hate or Set Adrift is much more likely than getting 1 out of 4 Duskmantle Guildmage AND 1 out of 4 Mindcrank (plus 1 out of 4 Mesmeric Orb against Leyline of Sanctity) every single game (and it is the only relevant factor since it's unlikely that the games where your graveyard hate or Set Adrift are not enough to win exceeded the times when you couldn't get the combo to begin with).
Here we try to assess ways to compensate for Mill's structural clunkiness - difensively or with the aim of bumping Mill's speed up alike - and understand under what circumstances they should suit our needs.
Jace's Phantasm, the most notably of them, is a defensive card that has the advantage of becoming a threat if the opponent stumbles (badly); but it is useless in far too many matchups, while where useful it is still marginal (it is a gamebreaking defence card if, again, the opponent stumbles badly). All in all, creatures either to block or to attack (even if they offer an alternative way to win) are glaringly ineffectual: opposing strategies can either swarm the board with creatures or cast a removal after having played their relevant threat (Tarmogoyf, Affinity/Infect/Zoo ones..) - this way they even suffer from no tempo loss, because the opportunity cost to cast a removal spell at that point is negligible: they can win with what they have on the board, and playing additional creatures would hardly affect the turn in which they threatened letal damage. Also, creature decks usually have their ways of making blocking creatures obsolete - by having huge trampling creatures (like Aura's ones) or unblockable/color-protected ones (like the ones from Infect, or because of Islandwalk from Merfolks). (As a little note, direct-mill spells like Breaking / Entering are obviously better than Mesmeric Orb with something like Jace's Phantasm or Wight of Precinct Six, while the artifact on the other hand reduces actively the cost for delving the likes of Gurmag Angler: there is little of a conflict here regarding the mix of mill spells you should employ.) Remarkably, blockers are easily redundant and superfluous in the defensive role if something like Fog is reckoned on as part of the plan for staying in the game. Finally, creatures are detrimental in the control/midrange matchup (they get to keep removals even post side since they don't have much better to bring in), against which normally the plan is to take advantage of Mill's difficult-to-disrupt gameplan (i.e. it wins by means of spells) and redundancy; defensive slots (main- or sideboard ones alike) are better used to cover up holes in the strategy, as opposed to playing creatures and then having still to deal with creature-decks post side as well as with the other common issues.
Because we tend to feature at least a little less defence cards than a reactive deck, the opponent will hold superfluos threat in hand at no cost (i.e. if they would not affect the turn in which she threaten to win, even playing around potential spot-removals): this way they can play around potential mass-removals or Mesmeric Orb (because of the lands they would tap to cast the creatures). So in the best case scenario, against a capable opponent who deploys but the needed resources, since the opponent can eventually cast the creatures held in hand until then, Damnation and the like could do no more than granting a land drop - not even acting as a fog (i.e. a time walk, in our deck) because you couldn't play your extra spells (the ones you couldn't simply play in place of your defence spell) neither in the same turn (as we could with Darkness) nor in the following one (as with a proper Crypt Incursion). And at worst, Damnation is completely useless because, apart from the kinds of disruption that could thwart your fogs too, it is weak to haste or flash(ed) creature or manlands, which make our efforts much less rewarding because we would likely be at very low life at that point; here are some: Goblin Guide, Monastery Swiftspear, Snapcaster Mage, Vendilion Clique, Spell Queller, Restoration Angel, Collected Company, Chord of Calling, Through the Breach, Aether Vial, Mutavault, Treetop Village, Raging Ravine, Hissing Quagmire, Shambling Vent, Stirring Wildwood, Celestial Colonnade. Mass-removals work well with Crypt Incursion in that they both feed it and prevent your opponent from committing too much to the board - making Crypt Incursion even greater - so they are really good if you can afford to play so much defensive spells that you could consistently cast 2 or more of them along the course of any game. In other words, as I said, a competent aggro player won't play into it, all the while still being able to represent lethal damage at a relevant turn; they would however be encouraged to commit more to the board if they knew of Crypt Incursion, but if you have Crypt Incursion in your deck either it shouldn't be there (it is bad against most opponents if you don't play another defence spell before it, and it is a bad choice if when it is good you would also win with any other card) or you are sporting so much defence that they could simply slow their clock down and commit less. Nonetheless, a mass removal seems a good play in some scenarios out of the Human matchup (the ones with certain combinations of hatebears), but rarely critical even there because of everthing we said - which makes it overall very narrow and probably just too small an upgrade over some other sideboard card.
We simply cannot consistently/effectively follow up the removal spell with other spot-defence cards and/or blockers or mass-removals because of the dedication of slots a mill strategy requires: defence cards in Modern are typically of a too wide use and little effect (like Fatal Push or even Path to Exile) or too narrow (like Stony Silence or Phyrexian Unlife) to produce an effective defence against the many strategies available in Modern - or at least slow them down long enough, taking also into account sideboard games. Actually, this is something even a dedicated control deck can hardly accomplish; let alone Mill, with only a few slot reserved to defence! And if you manage to squeeze in more slots, it would be like a Burn deck playing 12 Path to Exile-like cards - blatantly inconsistent! The alternative to comparing Mill to Burn is slowing the plan enough to make big plays (like Snapcaster Mage, or Startled Awake ); but again this is not possible as you would sorely need an engine of some sort (either milling or drawing) but at that point you wouldn't play Glimpse the Unthinkable. Since we cannot back up our removal spell following it up with another defence play, we actually cast that removal spell in order to gain tempo and not to control the board; and since the tempo given by a removal spell is at most one turn (foremostly if played in the very first turns) because of redundancy/protection, there is hardly a reason to play them over fogs - which at least gain you a turn unconditionally. Removal spells against an average creature deck (Zoo, Merfolk, even Burn), against which spot-removal should be meant, is good only in the first or the second turn (and, incidentally, you usually cannot do it on the second turn because you have to do other things as a lot of cards we cannot avoid to play cost 2 or more). Against those decks, the 'value' (of exchanging one card - our removal spell - for an opponent's card of our choice - her most threatening creature) that can be gained in later turns means nothing if you cannot survive. Thus that value is certainly not intended as preventing a combo or gaining some time, which are welcome outcomes we actively seek to get from our defence; similarly, against decks with few or problematic creatures we can surely bring in spot-removals from the sideboard. In other words: we don't have room for removal because we need space for mill: we need to resolve five mill spells milling 10+ cards in order to attain victory, and if we are not dense enough in the mill spell department we would lose the extra turn(s) hardly gained through our cheesy defence. Please note that I am not saying that playing removals in Modern is bad. I am claiming that spot-removals are generally bad when employed as part of the main defence plan in a Mill deck, where they are meant to gain their caster multiple turns - though sometimes they are a nice support out of the sideboard. Despite all that, spot removals can find their way in the maindeck as a tempo play in order to complement your fog suite if need be - though much worse because it accomplishes something useful only in the temporal window of turn 1-2.
Not fitting painlessy into your curve, it is very unlikely that Ensnaring Bridge could give you the little push you need in order for you to win (mostly) on the back of your mill spells alone: there is no chance you could play it casually in the maindeck. The reason is that, ideally, we would go turn-2 mill spell, turn-3 Ensnaring Bridge (with still 4-5 cards in hand), turn 4 double mill spell (2-3 cards in hand); 0- and 1-mana spells (not recycling themselves) would but mostly make up for hands when you don't curve out perfectly: in any case, we couldn't come up with a useful effect (against most decks we need that kind of defence against) from