The goal here is to control the board for a few turns while you set up your land before devastating their deck to finish them with mill spells.
On the first few turns, you want to get clean mana base up while milling them a bit with Hedron Crab's landfall and controlling the board with blue instants. You can use this in conjunction with Jace's Phantasms or Hover Barriers to provide solid flying walls. 1 landfall and a turn 2 Breaking is enough to proc the Phantasm's bonus stats. Oboro is included because can be used to landfall itself if you somehow do not have another land to play that turn.
Use Trapmaker's Snare to grab Archive Trap if you don't already have a copy, then Ghost Quarter one of their lands. If they choose to search for a replacement land, hit 'em hard with the Archive Trap(s). If they refuse the offer, you've slowed down their tempo even further! If you have milled 20-30 cards, you can very likely devastate them off with Haunting Echoes, while will exile all duplicates in their library (including nonbasic lands!). Finish them off with a few more mills and the game should be over! Keep in mind that you don't want to cast Haunting Echoes unless you're quite certain you can finish them off, because it will very likely remove Jace's Phantasm's stat bonus, and will likely also remove the extra draws from Visions of Beyond, as only basic lands will be left in the graveyard.
Unfortunately, getting the correct draws is not extremely consistent. Especially if you're forced to blow Echoes early, Visions of Beyond won't net you very much. For this reason, Consult the Necrosages is added in for the flexibility in keeping your momentum by either providing a decent discard or solid draw. If you're against aggro or other control decks, it's likely you'll need to swap out cards for more creature control in the sideboard. Ensnaring Bridge would be ideal here if you're able to run a thin hand.
Side/Maybeboard: Using fetchlands or Evolving Wilds will definitely double your crab value, though this may slow down your own tempo quite a bit with tapped lands (Evolving Wilds), or be dangerous if you're against burn (fetchlands). If you are against burn/aggro, you may need to swap in Crypt Incursion over haunting echoes. It's not nearly as devastating for the purpose of mills. Languish is also good here, because it provides solid AOE clear for 4 mana that Jace and Hover Barrier can both potentially survive. If you're CRAZY, cast Mutilate while Urborg is out, and watch it all burn. The Witchbane Orb is also good vs direct burn/targeted player spells.
Acquireboard: If you have Glimpse the Unthinkable, use it! Straight upgrade over Breaking because we don't have the red mana to be casting the Entering half anyways. As mentioned, fetchlands like polluted delta will double your crab value, but you'll be in danger of more burn (probably worth it). Inquisition of Kozilek can help tune the board to your favor early game by removing them before they're even played. Additionally, having a Snapcaster mage in conjunction with cards like Fatal Push or or even Tragic Slip can be some strong cheap removal if you flash them in to defend, and follow up with casting one of them. I know, all these cards expeeeeeensive, so that's why I don't have them listed in my paper main either.
Let me know whatcha think!
