85th floor
The group cleared the 82nd floor, and they found the entrance to the 83rd floor on one of the volcanoes.
The time that they consumed just to clear this single floor was four days. It was an exhausting battle for the rest of the team, as the enemies that they fought were B-rank and A-rank. Fortunately, the movements of the golems were predictable, so they could fight two or more A-rank golems at the same time. Still, it was tiring, as the golems that were guarding the entrance to the 83rd floor were S-rank.
On the 83rd floor, the setting was still the same. There were active volcanoes around the whole floor, but the temperature was definitely higher than the 82nd floor. Also, the golems here were much more powerful, and their movements were complicated.
A single B-rank golem from the 83rd floor could easily destroy five B-rank golems from the 82nd floor.