This is a lot of fun and can even help you learn to key faster, and it makes keying fun. All you have to do is type the word that the zombie says and your accomplices will shoot them. It goes the same for collecting health and using bombs that appear as well. Pick the level of difficulty you want and help a group of scientist make it to the space shuttle. They accidentally had a leak of some chemicals that has turned everyone into zombies and now they must get out of there before they are turned or killed.