The Doctor, Regenerating

When The Doctor, Regenerating enters the battlefield, reveal cards from the top of your library until you reveal a Time Lord Doctor creature card. Exile that card, then put the rest on the bottom of your library in random order. The Doctor, Regenerating becomes a copy of exiled card.
If The Doctor, Regenerating would be put into the graveyard from the battlefield, return exiled card to the graveyard and exile The Doctor, Regenerating instead.