Kill zombies to protect civilians. Zombies falling on the ground can get up again. So you have to be careful. Zombies will be faster in some levels. When the zombies get too fast, you can use the slow down button. There are multiple levels and each level only gets harder!
Zombies are mutated or biologically deformed beings that lose the control they once had over their body. So you have to save yourself from all the zombies!