Soulflayer

Most delve creatures treat the graveyard as fungible fuel: any card exiled pays for , and what gets exiled is irrelevant. This demon reads the bin instead. Every creature you exile to shave the cost can also donate one of eleven keywords off a fixed list, so paying and building are the same act, not competing ones. Exile a flyer and you both pay for and hand the 4/4 flying; feed it the right corpses and it arrives flying, trampling, lifelinking, deathtouching, and indestructible, a stack of evasion and protection assembled entirely from cards that were never going to be cast. The number that matters here is quality, not quantity. A yard stuffed with vanilla bodies gets you a cheap beater; a curated one gets you a threat that trades with almost nothing, survives most removal, and forces defenders to have flying or reach just to stand in front of it. The exiled fuel and the payoff are the same cards, which flips the usual delve calculus: dumping creatures indiscriminately weakens the graft, while seeding specific keyword-bearing bodies into the graveyard is the whole engine. Among delve cards, this is the rare one where the identity of what you exile carries as much weight as the count.