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Boarding action is a big team-oriented, symmetrical map from Halo: Combat Evolved. The entire map is comprised of two large UNSC space craft with exposed hulls docked side by side. There is just enough space between the two vessels to prevent commuting between them. However, each of the four levels of the craft are equipped with teleporters that can get you from one ship to the other.

This is a good map for CTF, but slayer variants can be just as rewarding. It is crucial to control the sniper rifles on this map, as well as the shotgun and rockets.