Name:Identity Thief
ManaCost:2 U U
Types:Creature Shapeshifter
PT:0/3
T:Mode$ Attacks | ValidCard$ Card.Self | Execute$ TrigExile | TriggerZones$ Battlefield | OptionalDecider$ You | TriggerDescription$ Whenever CARDNAME attacks, you may exile another target nontoken creature. If you do, CARDNAME becomes a copy of that creature until end of turn. Return the exiled card to the battlefield under its owner’s control at the beginning of the next end step.
SVar:TrigExile:AB$ChangeZone | Cost$ 0 | ValidTgts$ Creature.nonToken+Other | TgtPrompt$ Select another target nontoken creature | Mandatory$ True | Origin$ Battlefield | Destination$ Exile | RememberLKI$ True | SubAbility$ DelTrig
SVar:DelTrig:DB$DelayedTrigger | Mode$ Phase | Phase$ End of Turn | Execute$ TrigBounce | TriggerDescription$ Return exiled permanent to the battlefield. | RememberObjects$ Remembered | SubAbility$ DBClone
SVar:TrigBounce:DB$ ChangeZone | Origin$ Exile | Destination$ Battlefield | Defined$ DelayTriggerRemembered
SVar:DBClone:DB$Clone | Defined$ RememberedLKI | CloneTarget$ Self | Duration$ UntilEndOfTurn | SubAbility$ DBCleanup
SVar:DBCleanup:DB$ Cleanup | ClearRemembered$ True | ClearImprinted$ True

SVar:Picture:http://www.wizards.com/global/images/magic/general/identity_thief.jpg
Oracle:Whenever Identity Thief attacks, you may exile another target nontoken creature. If you do, Identity Thief becomes a copy of that creature until end of turn. Return the exiled card to the battlefield under its owner’s control at the beginning of the next end step.