My Undead Horde Awakens | Magic: The Gathering
Formats My Undead Horde Awakens is Legal in
Official Oracle Text for My Undead Horde Awakens
At the beginning of your end step, you may put target creature card from an opponent's graveyard onto the battlefield under your control.
When a creature put onto the battlefield with this scheme dies, abandon this scheme.
Official Rulings for My Undead Horde Awakens
6/15/2010 : When this scheme is abandoned, nothing happens to the rest of the creatures that were put onto the battlefield with it. They simply remain on the battlefield.