Identity Thief

Identity Thief will still be a copy of the creature during the next end step when the exiled card returns. If it has an ability that triggers at the beginning of the end step, that ability will trigger for Identity Thief and not for the returned creature.

Noncopy effects that have already applied to Identity Thief will continue to apply to it. For example, if Woodcutter's Grit gave Identity Thief +3/+3 and hexproof earlier in the turn, Identity Thief will still have those bonuses after copying a creature.

This effect can cause Identity Thief to stop being a creature. For example, if you target an animated Gideon Jura (a planeswalker with a loyalty ability that turns him into a creature), only the printed wording will be copied; the “becomes a creature” effect won't. Identity Thief will become a noncreature Gideon with no loyalty, be removed from combat, and then be put into its owner's graveyard.