Contained in a metal dome with a glass skylight would be the Blazing Arena, warm temperatures are spread throughout the dome by two everlasting streams of fire. The heat warms up the metal walls and floor after some time, so caution and protective footwear are definitely recommended. Prolonged exposure can lead to early symptoms of heat exhaustion. The water vents are typically boiling and the earth disks can absorb the heat as well. It is forbidden for any participant to attempt to break the skylight in any way.
With these rooms, dice rolls can be performed by participants. Be warned that these rooms contain logs, cheat and I will know. Simply put #d5 and you'll perform a roll. Links can be found in the comments section.