Painkiller

Stranded in a place between Heaven and Hell, your time of judgment is at hand. The Underworld is on the verge of unholy war, and you are but a pawn in the infernal battle. As you fight for your purification, the truths behind the deceptions are revealed. Painkiller puts you in a nightmarish world where monsters swarm you in mobs. Eliminate your enemies using a variety of weapons and using your power to morph into a possessed creature.

Painkiller is a shooter/horror game available on PC.