Combat Experimentation Room

A large room hidden under the House of Evolution headquarters, locked away under a metal trapdoor.

Plot
On entery of this room there is a long underground tunnel that leads from the metal trapdoor entrance, all the way to the huge white room.

The combat experimentation room is the largest room in the facility. It's also the location of where Genos vs. Carnage Kabuto and Saitama vs. Carnage Kabuto took place. Originally used to test fighting and experiment combat (as in the name of the room), but eventually became a place to contain Carnage Kabuto as he was too powerful for Dr. Genus to control and incase he ever went berserk.

On lockdown after Carnage Kabuto turns "Carnage Mode" the entrance to the room shuts with powerful containment doors, the lights turn off only leaving it to go dark and to trigger the red emergency lights with an alarm sound going off on activation.

After Carnage Kabuto's death the room went back to it's normal white self, though a huge hole is left in one of the walls after Saitama punches through in hurry to get to a sale at the supermarket. A forest is seen from outside the hole, showing that it's on the inside of a cliff.