Undercroft is one of the very few completely indoor maps. The layout consists of three levels, with the third being a small walkway. However, players can also land ontop of the pillars, and on some of the ledges of the columns. There is a grav-lift that connects the ground floor to the second level, and several chutes that connect the three levels. Based on the iconography, this structure belonged to the Children of the Phoenix. This map is available in Arena mode only.