Shang didn't stay in his hole for three entire days. Obviously, he left pretty quickly and joined the barbarians in their rampaging.
He wasn't very interested in killing people and beasts much weaker than him, but he joined a couple of battles against Peak General Stage Summoners and beasts just for training.
About a day later, Shang left the barbarians as they continued ravaging the lands and returned to the Mages.
The Mages had already started to rebuild the black castle and were reorganizing it as a new base for operations.
As Shang reached the newly rebuilt gates, he was stopped by two True Mages, who looked at him with disdain. "Barbarians are not allowed in here," one of them said.
"Researcher Veral told me to return to him after the mission," Shang said.
The two Mages looked at each other with furrowed brows.
One of them snorted, but they let Shang pass.
"Researcher Veral is inside the basement," one of them said.
