Killer Instinct

Oracle Text

At the beginning of your upkeep, reveal the top card of your library. If it's a creature card, put it onto the battlefield. That creature gains haste until end of turn. Sacrifice it at the beginning of the next end step.

Card Rulings

2/1/2006 If the top card of your library isn’t a creature card, it remains on top of your library. You won’t have to sacrifice it at end of turn.