Jason Chen is a Taiwanese soldier, and a Champion in the Fourth Great Games of the Hydra.
Captain Jason Chen of the Taiwanese Army had apparently built up a reputation as a great soldier, and because of this he was selected by the King of Sky, Kenzo Depon, to be one of his four representing Champions during the Great Games of the Hydra.
However, Chen was unaware of this decision or even of the existence of the Games, and a short time before the Games were set to commence, he was kidnapped (and likely drugged) while he was still sleeping in his barracks. He was then taken to the Underworld, along with a few of his friends/family who were to be his hostages, and had an explosive device implanted in his neck.
Chen, like the other participants in the Games, awoke in a strange cell to find himself confronted by a strange man in a bull-shaped helmet. After killing his opponent, Chen ventured out of the cell to find himself among thirteen others who had succeeded against their enemies. They were then all confronted by the man calling himself Hades, who explained that they were all participants in the Great Games of the Hydra.
Chen interupted Hades during his speech, claiming that he was here against his will and had no desire to participate in the Games. Hades was surprised at this, and so Chen began to repeat his desire to leave, at which point Hades' games master, Vecheron, detonated the explosive in his neck. Chen's hostages were summarily executed just a few moments later.
With Chen's death, the other unwilling Champions in the Great Games realised that they had no choice but to participate or else they and their hostages would be executed like Chen.