The day before, in the fighting arena of the Outer Block, the disciples were left quite shocked by all the events that happened. Arslan utterly humiliating Jacob, who was the third in the outer ranking, Eliza's return, the discovery of Troy's and Jacob's plan to have Arslan accept the challenge, and Eliza showing once again why she was the nightmare of every disciple who had to fight against her.
They also clearly saw the open disagreement between Elder Song and Elder Oak, who were two of the most powerful elders of the Academy, even if Elder Song was still stronger than the other. With all that in mind, they came out of the arena with pale faces and the realization that a lot of things were happening without most of them knowing.