About this game:
Retro shooter action and RPG elements are combined in this new downloadable third-person shooter. God Mode combines non-linear gameplay, fast and frantic shooting, hordes of on-screen enemies, a fully functional online coop mode, and features visuals and gameplay that rival that of a full-priced boxed title. Matches rarely--if ever--play out the same, as dozens of in-game modifiers can significantly alter the gameplay on the fly. Characters are fully customizable, both in appearance and equipment, which continually evolve. Gold and experience are constantly accrued and used to unlock new and satisfying weaponry and unique powerful abilities, both of which can be further upgraded.

Do note its an unguaranteed key, I just know what it is because I already own it.