Introduction
When I first read the card Reaper King I knew that the Vindicate effect of the card was too valuable to pass up. However, the card is clunky. It costs a lot of mana to be competitive, and worse it's five colors. But powerful enough to take seriously. This deck is essentially designed to destroy all of your opponent's permanents, and I usually start with the lands.
This deck is designed to get Reaper King out onto the battlefield as soon as possible, then start playing Scarecrows to trigger the Vindicate effect and remove your opponent's lands. Unless there's a threat on the board, in which case the effect can be used to remove whatever you like. And with the benefit of speed and cards like Cavern of Souls you can protect yourself against counters. The deck is able to do this in many ways, with the ideal set up having Reaper King on the battlefield and a method to produce infinite mana with scarecrows in hand by turn 3. All of the ways to do this will be outlined below.
If the combo is disrupted, however, the deck can still protect itself with going wide and creating some light card advantage, along with tons of mana.
The Game Plan
1. Get Reaper King out on the battlefield Turn 3-4 by taking advantage of one of 4 different methods.
The first (and ideal) is to use Pentad Prism to accelerate the mana on turn 2 so you have 5 potential mana on turn 3. The deck has several ways to produce mana of different colors, including Mana Confluence, Breeding Pool, Blood Crypt, a handful of basics and even a play set of Cavern of Souls. Although the Cavern of Souls is more useful on stage 3 of the game plan to prevent the Reaper King trigger from being countered, but we will get to that in a moment.
The second is to use the pili-pala + grand architecht combo to produce infinite mana of all colors. This can be done by using the Grand Architect's abilities on Pili-Pala. First, you make Pili-Pala blue, then you tap it and add two colorless to your mana pool. After, you then activate Pili-Pala and pay using the two generated from tapping him, netting you one mana of any color. Use this to produce one of each color to get out Reaper King and then to play every scarecrow in your hand, hopefully to take out all of your opponent's permanents.
The third is to use the effect of Call to the Kindred. On turn 2 you might have played something like Painter's Servant in the hopes of setting up an infinite mana combo using Grand Architect, but instead draw a Call to the Kindred. Unless you can complete the infinite combo, your best play is to use the Call to the kindred to hopefully sneak out Reaper King a turn earlier than he's supposed to join in the game.
The fourth method is simply to cast him at his cost using the effects of cards like Scuttlemutt, Cavern of Souls, Mana Confluence, and the Shock/Basic lands that are in the deck. As a side note, you can use Polluted Delta to search for any land that you need to produce the color you are missing since all of the dual lands have either the Swamp or Island type. It's best if they enter untapped. Don't worry about the life cost. Up to 3 life to pay is a small price This is the least ideal method but it can still get him out on turn 4, which is not bad for his power and effectiveness alone without even mentioning the triggered effect.
2. Generate tons of mana.
While the mana accelerators are ideal for use in the early game, they also come in handy in mid to late game. Pentad Prism for example could be the difference between destroying one of your opponent's permanents in a single turn, or destroying two in that turn. The difference is quite significant. The other helpers are Scuttlemutt, and the infinite combo of Grand Architect + Pili-Pala
as well as just the effect of Grand Architect itself giving 2 mana to cast artifacts. Which, lucky for us, all scarecrows are artifacts. As well, the Painter's Servant can help to activate Grand Architect by saving one blue mana. It's even better if you already have several scarecrows on the field which is more than likely at this point.
3. Destroy all of your opponent's permanents.
In addition to assisting with combos and combat damage, cards like Pili-Pala, Painter's Servant, Scuttlemutt, and Scarecrone are also all Scarecrows. Meaning they trigger the main effect of the deck by making your Reaper King Vindicate all over your opponent's stuff. Couple this with the aforementioned mana acceleration, and card draw effects such as those from Scarecrone and Chromatic Star and you have the tools to be taking out more than one permanent per turn, and since permanent applies to everything on the board you can assess your threats quite easily, or just rid them of their mana.
Hard casting, however, is not the only nor even the most efficient method for bringing scarecrows onto the field. As mentioned before in step 1, Call to the Kindred is a valuable tool. After all, what's better than destroying a permanent during your turn? Having it happen automatically at upkeep. And since the only creature card in your deck that is not a Scarecrow is Grand Architect, the odds are in your favor that the top 5 cards will have at least one of what you need. If you can get two Call to the Kindred online, your opponent might as well concede. Searching the top 10 cards of your library for up to two permanent destroyers and putting them on the field during upkeep is exactly as powerful as it sounds. And if you don't find one, well guess what? Chances are you're going to draw it during your turn. Remember, the effect of Call to the Kindred tells you to put the remaining cards on the bottom of your library, meaning if you don't find what you need, you've filtered through 5 cards increasing your odds of drawing what you need during that turn.
4. Go in for the kill
At this point your opponent should have next to nothing on the board, and probably not a lot going on in their hand that can stop you from taking action. The threat of Reaper King and his 6/6 power and toughness is strong on its own. But the fact that he also happens to be a lord who will pump all of your other creatures except for one is also extremely useful in creating a wide threat. As for grand artificer, he may not be a Scarecrow but he pumps all other blue creatures... including Reaper King who, in addition to being everything else is blue. Now, if you've combo'd out with Grand Architect + Pili-Pala
with the added help of Painter's Servant making everything blue, then grand architecht pumps everything along with Reaper King.
Pumping is not the only important thing. That's why we also have Jawbone Skulkin. Not only does he function as a cheap scarecrow to trigger Reaper King with, he also has the ability to give Reaper King haste, allowing you to swing in a tear earlier than is going to be expected by your opponent.
The Remaining Cards and Sideboard
More Destruction
The theme of the deck is to destroy permanents so Maelstrom Pulse is an excellent edition. If you're fighting something like Merfolk or any deck with multiple copies of the same nonland permanent, then this card is your friend on turn 3. And there's plenty of ways to produce the necessary Golgari mana to cast it. With 2 in the sideboard in case you're playing a deck where buying time to get your combo is more important than setting up a threat. I would switch out two Painter's Servant for the Maelstrom Pulse in that case.
Cantrips and Setting up your Hands
Finding what you need and setting up your draws are extremely important to this deck. That's why we have two acnient stirrings on the main board along with three Serum Visions. With the exception of grand architecht and Reaper King, all of your cards are colorless so finding the piece you need is pretty easy. On the sideboard there's another Serum Visions in case three don't prove to be useful enough.
Needing to draw cards becomes important with this deck on occasion in mid-game decisions. Sacrificing Scarecrone to itself or using a Chromatic Star (floating whichever color you are missing) can help you get ahead quickly. In the sideboard there are also two Ancestral Vision which can certainly come in handy against a heavy discard or control deck.
Defense
Early defensive strategies can be important if you're dealing with a deck that has a bit more speed than this one. The aforementioned Maelstrom Pulse can definitely help but there are a few more options. We have two copies of Dismember, two copies of Thoughtseize, and two copies of Ratchet Bomb.
Also on the sideboard is two copies of Damping Sphere to shut down Tron. Though, this deck is quite good against tron since you can just take out one land and shut the others down. But Damping Sphere is a credible threat and will buy you plenty of time while you wait for the opponent to find an answer.. by which time, they will be dealing with a much bigger threat.
Conclusion
Thinking through the design of this deck has been great fun. The deck is rather complicated and not easy to pilot since the strategy has to shift on the spot. But it's very fun to play and gives you the feeling of really having to think through your opponent's moves and plan yours ahead accordingly.
