Qarsi Sadist
Exploit turns sacrifice from a cost into a trigger, and this is the drain payoff that justifies feeding it. Most exploit cards ask you to give up a creature for some incremental return; the return here is a four-point life swing (two drained, two gained) the instant the sadist enters and eats something. The toughness is the quiet part of the design: a 3 on the back lets it survive the small-creature combat these decks live in, so the thing you sacrifice can be a token, a dying utility creature, or a creature whose own death trigger you wanted anyway, while the sadist stays back to block. That stacking is where the mechanic earns its slot: one entry can resolve a sacrifice effect, a death trigger on the exploited creature, and the drain, all without a dedicated outlet on the board. The clause is gated by "may," so a board with nothing worth feeding still leaves you a defensive body rather than a dead card, which is what separates a build-around payoff from a liability. It belongs to a black tradition of converting creatures into reach: drain priced to punish the opponent with the same resource you were already spending, in the lineage of effects that close games by attrition rather than combat.
