The Sky Battle Tsuna's old adversary, Mukuro Rokudo, has successfully fought on the side of Tsuna's "family" for possession of the Mist Ring. But his opponent, the Varia known as Mammon, has a highly developed sense of never-say-die! Later, Tsuna finally completes his training and returns in time to confront one of the Varia who is running amok. The whole game changes, however, when he finds out who this Varia really is!