Although this game rates very high on the reviews If you want to run it on a PC without a controller forget it. Terrible port.
You will need to splash out on a PC controller just to try to play this game.
The keyboard/mouse controls are terrible. Slow character rotation using A & D only, no strafing L/R movement and cannot move freely with mouse & W/S like you are probably used to and take for granted. So if you are expecting the sort of character control you get with almost all the modern PC games you will not find it here. A huge game breaker.
Aiming using Mouse right button & Mouse is also jumpy and just feels unresponsive.
Very linier gameplay.
All in all just Don't buy it. If you want to run a Zombie game on PC try State of Decay.
for me it's time to uninstall this and confine to the bin.