Fermentus, Master of Decay

Fermentation — Whenever Fermentus deals combat damage to a player, you may exile a card from their graveyard. If you do, create a token that’s a copy of that card.
Distill Power — Sacrifice a creature: Fermentus gains control of target non-token creature until end of turn. It gains trample and lifelink until end of turn.

Tap, Sacrifice Fermentus: All opponents lose life equal to the number of cards in their graveyards.