what surprised Bastian when he fought the guards in the cellar

Atreyu puts on Bastian's silver mantle and distracts the guards while Bastian sneaks into the castle. He finds the heroes chained in the dungeon, dangling over a bottomless pit. He frees them from their chains and then battles countless metal giants. Instead of escaping the castle, Bastian seeks out Xayide to confront her. Xayide stares at him with her mesmerizing green and red eyes, and then lowers her head. She begs his forgiveness and swears to be his humble slave if he will spare her life. Bastian is moved by her flattery and insists she join his party. Falkor refuses to carry Xayide out of the castle, but Atreyu convinces him. However, Atreyu warns Bastian that Xayide is conning him. Bastian is so angry with Atreyu that he orders him and the luckdragon to leave.