Rotlung Reanimator

The name promises graveyard recursion, but the real engine is cleverer: a death trigger that converts a dying Cleric into a fresh body, and the body it makes is a Zombie, not a Cleric. That asymmetry is the wrinkle the combo crowd seized on. Read alone the trigger is narrow, gated to a tribe that rarely floods the board, but pair it with one effect that calls every creature a Cleric and the trigger starts feeding itself: a Cleric dies, a Zombie appears, that Zombie is also a Cleric, and a free sacrifice outlet sends it back to die again. The chain is a strict one-for-one (the token you sacrifice is replaced by exactly one new token), so the engine never nets bodies. What it nets is iterations: each loop pumps a fresh sacrifice activation and a fresh death trigger through the system, and those repeatable activations are the payoff, not a growing army. Bolt the right outlet to the loop and you can drain a table, mill a library, or fuel any death- or sacrifice-counting engine arbitrarily many times. This is the emergent machinery a tribal-matters design era invites: gather enough creature-type-rewriting effects in one place and players will weld them into engines nobody scripted. The 2/2 is incidental. The instant a type-rewriting permanent and a free sacrifice outlet share the table, this becomes a faucet you can leave running.