Every member of Hiro's party (except for the man himself) is a serious case of Brilliant but Lazy, with their leader being the only reason they do anything productive on the first place! Kill him, and everyone goes back to playing videogames and goofing around.
Zig Zagged: Sometimes, when Hiro falls, the battle goes on; sometimes the battle falls, and it's all about random chance.
Averted: Hiro can be revived during battle with no ill effects.
Played For Drama: Because Hiro has fallen, his allies immediately stop fighting and the enemies are able to slaughter every single one of them. If only Hiro had stayed alive, the good forces would have won in the final battle against the Big Bad.