Dawn of the Dead

Oracle Text

At the beginning of your upkeep, you lose 1 life.

At the beginning of your upkeep, you may return target creature card from your graveyard to the battlefield. That creature gains haste until end of turn. Exile it at the beginning of the next end step.

Card Rulings

10/4/2004 The creature is only exiled if it is still on the battlefield at the beginning of the end step.
8/1/2008 If the creature leaves the battlefield, but returns to the battlefield before the triggered ability resolves, you won’t exile it. This is because it is treated as a different object than the one to which the ability refers.