Steam Achievements [...]
The game provides co-op zombie-killing for up to six players at a time, with unlockable persistent perks to level up your character. Add in Solo mode for offline play, more than 15 weapons, 9 zombie types, slow-motion ZEDtime. Shotguns, chainsaws, flamethrowers… not to mention a machete, fire-axe and much more. Weld doors shut to try and channel the specimens, buy time to heal up and reload. Even configure your own waves of zombies with the in-game tools “ or use the SDK to create complete new maps to play on.