Enfo's Team Survival is a popular modification for Warcraft III: The Frozen Throne. It was originally developed by Enfo, but has since been released openly and is being continued by many modders. It is loosely based upon tower defense maps. Players are divided into two teams and choose their heroes at the start of the game. They cannot directly engage in combat with the other team. Instead, they fend off waves of monsters in order to survive for longer than their enemies.