Experiment Four O' Four

Each player puts the top five cards of his or her library into his or her graveyard. Then, return a creature card at random from an opponent's graveyard to the battlefield under his or her control. It's a black and green Zombie in addition to its other colors and types.
"This will definitely be logged a failed experiment. I
had no idea the corpses would retain any sense of loyalty to their prior masters. We'll just Try Again."
- Gast, Baffled Stitcher