From the publisher's website:
Welcome to the dark side of Fluxx, the card game of ever-changing rules! Zombie Fluxx takes the award-winning card game Fluxx and cranks up the fun with a Zombie uprising. The Zombies arrive in the form of a new type of card, called the Creeper, which hangs around in front of you, preventing you from winning. The good news is, the Keepers include a Shotgun and a Chainsaw and various other things you can use as weapons against the Zombies. Plus you've got Sandwiches and Coffee and a couple of Friends to help you win. The bad news is, if your Friends become Zombies, you'll have to destroy them!