Bloodtracker

The pump ability and the exit trigger are two halves of the same bet: you feed it black mana and life to grow the body, then the counters you paid for cash out as cards the moment it leaves the battlefield. That converts a repeatable investment into a delayed card-draw payload, so the creature is only worth as much as you sank into it before it left play. Each activation asks for both a black mana and two life, which slows the accumulation and doubles the resource strain: you are not just bleeding yourself thin, you are committing mana every turn that a fragile 2/2 flier survives. The tension sits in who controls the exit. Sacrifice it yourself on your terms and the counters become a clean refill; let an opponent kill it after five or six activations and they have handed you a fistful of cards for the trouble. Because the trigger keys off leaving the battlefield rather than dying, removal that exiles or bounces pays out the same way a straight kill does, so most answers still reward you. What keeps the whole thing from spiraling is the layered cost stacked against a body with no protection: every counter demands mana you could spend elsewhere and life you may not have to spare. The payoff scales exactly with the risk already absorbed, which makes it a slow, self-limiting draw engine wearing a Vampire's clothes.