Theo and his group spent a week cultivating inside the [Dimensional Room]. Thanks to this, Theo advanced to the 11th Layer of the Spiritual Realm while Yuki and the girls reached the 12th Layer of the Superior Wizard Realm. Mizuki, with the help of Theo, made it to the 4th Layer of the Spiritual Realm.
If you're wondering how Theo managed to help Yuki and the girls reach the Superior Wizard Realm's 12th Layer so fast... that was simple. He used the corpses of the Sect of Ten Thousand Souls disciples that they had killed and shared with all of them the essence of energy. Doing so allowed them to advance very fast.
Outside the [Dimensional Room], Theo and his group were surprised. Many things had changed, as did the structure of the arena. Not only did it get bigger, but it could also even hold up to 150 million people. It was also more reinforced. There were power poles in each of the four corners of the arena and the floor was made of white stones that seemed to be very resistant.