Move your character using the WASD keys and direct with your cursor. Attack zombies by pressing the left mouse button to eliminate them. Survive as long as possible by dodging waves of undead and picking up weapons and ammo. Upgrade your stats between levels to increase your strength and durability. Use the Tab key to access the menu and organize your gear. Team up with friends in co-op mode to last longer. Keep moving and go for critical hits to save ammo.