Welcome to Niven Experimental Labs ][ Special Edition...
An experimental orbital nuclear reactor sitting in an Earth - Moon lagrange point.
Advanced quantum singularity power sources provide enormous amounts of power and have allowed the facility to expand way beyond it's original design. The tournaments still have access to the labs as the station inhabitants insisted their favourite form of entertainment continued. The combatants now find that the arena has expanded and includes the twin air processing plants in addition to the reactor core.