Left 4 Dead is a cooperative first-person shooter survival horror game for the Xbox 360, developed by Valve. It pits four survivors against hordes of infected zombies in a post-apocalyptic world. Players must work together to fight through various levels to reach safe zones, using a variety of weapons and items. The game features an AI Director that adjusts the intensity and pacing of the zombie onslaught based on player performance, ensuring dynamic gameplay. Its blend of action and horror with a focus on teamwork makes it a standout title in the genre.