Venomcrawler

A death-triggered growth engine that reads the whole board as its ledger. The demon arrives small and stays small until the dying starts; the Devourer of Souls clause fires on every other creature death, yours and your opponents' alike, so a grindy attrition war feeds it one counter at a time regardless of who is bleeding fodder. The one thing it cannot exploit is the board wipe: this is a creature, and a symmetric Wrath sweeps it away with everything else. Its natural home is the slow game, the sacrifice loop, the edict trade, the token chump-block, all the incremental dying that black turns into profit. Lifelink is the payoff that ties the counters to a clock: every swing converts the accumulated corpse-count into a life swing scaled by however large the pile has grown, so a chump-blocker that entered as a nuisance can end a game as a drain-attached finisher. That fragility at cast time is the point; it functions less as a threat than as a tally, silently marking each death until the swing arithmetic tips in its favor. The design leans on black's oldest contract: profit from death, and the more indiscriminate the dying, the fatter the return, provided nobody reaches for the sweeper that takes the tally-keeper down with the tally.