Back in the 1980s and 1990s, Irem was a prolific Japanese game developer that produced numerous arcade and console hits. ININ and Strictly Limited Games have already announced Irem Collection Volume 1, a collection of single-player shoot 'em ups. Irem Collection Volume 2, however, features four games, all of which feature 2-player local co-op! The four games are GunForce (Arcade), GunForce (SNES), GunForce II (arcade), and Air Duel (arcade).