Quad Cannons are powerful anti-naval cannons that are capable of taking out a battleship in 4 to 5 shots. They have high health, impressive damage, but have an extremely slow rate of fire. When you arrive to protect them in the final BWII flashback level, Apocalypse, they are already manned and cannot be controlled manually. The mission is to protect them from the incoming Gunships, Battleships, and Naval Transports carrying light tanks.