Intro
This deck is built around a combo using Tree of Perdition and Turn to Frog. Including green would allow for Assault Formation and a deck like this Bluewallin - Sultai version of Unstoppawall Budget, but I think it dilutes the deck too much. Likewise, I think adding Triskaidekaphobia dilutes it too much as well.
Please let me know what you think in the comment section and give a +1 if you think this deck is worth is. I plan on revising the sideboard and further tuning the deck once the new meta settles.
The Combo
The goal of the combo is to use the Tree of Perdition exchange health ability when it has 1 health then to do 1 damage. One way to get the tree's health to 1 is to first use the exchange ability. Then, while the ability is on the stack, cast Turn to Frog on the tree. The spell will resolve first, changing the toughness to 1, then the exchange ability will resolve. Remember, abilities exist independently of the creatures creating them, and will still resolve even if the creature is removed (or transformed into a frog).
The other way to achieve the same result requires a tree in the graveyard and a Soul Separator in play. On the opponent's end step, use the divide ability and create a 1/1 flier with the exchange ability. Then pass to your turn and you can bring the opponent health to 1.
The second step of the combo is to do one damage. One way to do this is with Cryptolith Fragment
. When we tap it for 1 mana, it will damage the opponent for one, and it cannot be interrupted. Retreat to Hagra combined with Evolving Wilds could do this as well, but is less reliable. Sorin, Grim Nemesis can do the same, but you need a fragment in play to get the to cast him. IF you tapped out your fragement, then Sorin could be backup damage.
Control
The rest of the deck is mean to shut down the opponent while we set up our combo. We need to be able to resolve our tree and frog, and blue helps here with Spell Shrivel and Dispel. Duress and Transgress the Mind can also help get rid of their threats to the combo.
There is also removal to keep the opponent at bay using Ruinous Path, Grasp of Darkness, Ultimate Price and Languish.
The deck has several tools to get the right cards in our hand, including Read the Bones and Anticipate. Contingency Plan can help flip Jace, Vryn's Prodigy
and putting a tree in the graveyard can help enable a Soul Separator later.
Dark Petition is there to help tutor up a missing piece of the combo.
