Description: Help Zack to find what's going on in the biomedicine lab where he works. Move with the arrow keys. Press Q to open your inventory. Press the space bar to open the doors. Use the mouse to choose objects from the inventory. Make click to attack. Press R to reload your weapon. Press the Caps lock to turn the light on.. The Serum is a Zombie Games.
Instructions: Q - To choose weapon.
R - to reload.
W,A,S,D/Arrow keys - To move/jump.
Mouse key - To aim and shoot.
Space bar - To open doors/climb out..