瞬间
目标生物的操控者将它牺牲,然后将X个1/1,绿白双色的地精/战士衍生物放置进场,X为该生物的力量。
You target the creature that will be sacrificed when you cast Mercy Killing, then its controller (who may or may not be you) sacrifices it when Mercy Killing resolves. Because this is a sacrifice, neither regeneration nor indestructibile will save the creature.