Rule 112.6k

An ability whose cost or effect specifies that it moves the object it’s on out of a particular zone functions only in that zone, unless that ability’s trigger condition, or a previous part of that ability’s cost or effect, specifies that the object is put into that zone. The same is true if the effect of that ability creates a delayed triggered ability whose effect moves the object out of a particular zone. Example: Reassembling Skeleton says “{1}{B}: Return Reassembling Skeleton from your graveyard to the battlefield tapped.” A player may activate this ability only if Reassembling Skeleton is in his or her graveyard.

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