Warhammer 40,000: Kill Team is a twin-stick arcade shooter set in the Warhammer 40,000 universe. It casts the players as Space Marines attempting to destroy an Ork invasion space vessel. The players can pick one of four different classes for their Space Marines, from the ranged-focused Sternguard Veteran and Techmarine to the melee-focused Vanguard Veteran and Librarian.

Across the five levels in the campaign the player will move across various sections of the vast ship in an effort to sabotage it before it reaches the human world it seeks to conquer. Aside from facing the onslaught of the Orks the Marines will also have to deal with the terror of the Tyranid. Between these levels the player has the chance to level up his marine's equipment as abilities. The game uses a third-person, almost top-down perspective and supports cooperative games with a second player.