AWSOMENESS!!!! O_O
Thia game is the shit u have to make another one but with more gore like with each bullet that hits a zombie chunks of rotting flesh flys off them or something but yeah make another with an intro that explains the story. And u pay for ur upgrades or like the army pays u to kill zombies, MAKE MUTANTS
P.S if u dont make another ill eat your skin and sell the rest on the black market =D