Battle Spirit: Digimon Frontier, the fourth season of the Digimon anime series, premiered on Fuji TV in Japan.
Battle Spirit: Digimon Frontier concluded its original run on Fuji TV in Japan after airing its full series.
The English dub of Battle Spirit: Digimon Frontier was released in North America, expanding its audience internationally.
Takuya and his friends find the legendary Spirit Evolution and gain the ability to transform into Digimon Spirits.
The group fights Cherubimon's minions for the first time, defending the Digital World from his growing influence.
Mephistomon arises as a major antagonist, further threatening the stability of the Digital World.
Cherubimon is defeated in a decisive battle, but Mephistomon's threat remains.
Takuya and the team unlock Evo Spirits allowing enhanced transformations into Hybrid Spirits.
The ultimate battle to save the Digital World from destruction takes place, culminating in Mephistomon's defeat.
Takuya and his friends return to the human world, closing the portal and ending their adventure.