Shooting is with Ctrl. Space is to interact with something (open doors, activate levers, buttons, etc). Digits (1, 2, 3, etc) are to choose weapons (knuckles,

Shooting is with Ctrl. Space is to interact with something (open doors, activate levers, buttons, etc). Digits (1, 2, 3, etc) are to choose weapons (knuckles, pistol, shotgun, etc.)