3. Orcs Must Die! 2
Developed by Robot Entertainment, Orcs Must Die! 2 is a tower defense strategy title and sequel to the first Orcs Must Die! Unlike the first title, which was exclusively single-player, the game features an emphasis on two-player cooperative gameplay. Playing as either the War Mage or Sorceress, players must fend off waves of emerging orcs bent on reaching the heart of the level. Players can kill them by placing traps or beating them up personally.