Scathe

Scathe is a gory first person shooter where the titular Enforcer of the Legions of Hell must clear out the underworld of its unholy inhabitants. Hell is a large labyrinth which can be explored in whatever way you choose, the only requirement being that you collect Hellstones by killing bosses.

During your exploration of the Hell labyrinth, you'll gain an ever-increasing number of weapons and spells. Weapons each have a secondary fire as well, giving you even more options during battle. For some extra firepower, it's also possible to call in up to three friends for drop-in, drop-out co-op (though all players share the same pool of lives).