[Before Neoma and Ruto's encounter...]
JASPER had prepared himself for a fight when he reached the camp's Underground Arena.
But much to his shocked, the battle was over when he arrived.
[Just what happened here?]
The Underground Arena was a replica of a fighting coliseum in the Royal Capital. The camp owners would choose the strongest and most talented children and young adults that they "owned." Then, they would those children fight beasts that the camp also illegally collect.
When he arrived at the camp, Alistair Madgwick gave him a test that would prove that he wasn't there was a spy. That bastard asked him to surrender Tate, his cousin and closest aide, to be one of the fighters in the Underground Arena. Since he needed to gain the trust of Alistair Madgwick back then, he had to sacrifice Tate.