Press J to toggle invulnerability.
Your paranoia lead you to build an anti-zombie bunker. One day, the zombie apocalypse is finally happening! Equipped with deadly defense weapons, and the ability to upgrade the bunker the more zombies you kill, this is going to be awesome!
Aim & Shoot: Mouse
Reload: R
Missiles: A
Stun Grenades: S
Shields: D
Pause Game: P