Tower defense meets first-person shooting in Sanctum 2. Each map centers on oxygen-producing Cores that alien waves try to destroy; the player first builds towers to shape the enemy's route, then steps into the fight personally with a weapon when the wave arrives. Four character classes and a loadout system covering towers, weapons and perks allow different approaches to each map.
Because success depends on both layout and aim, the game rewards planning and good shooting in equal measure. It supports single-player and online co-op, where teammates can split the work between building and fighting. It suits strategy players who want more hands-on action, and shooter fans who enjoy designing a defense.