Digimon Frontier (Season 4)
Takuya Kanbara, Kouji Minamoto, Izumi "Zoe" Orimoto, Junpei "J.P." Shibayama, Tomoki "Tommy" Himi and Kouichi Kimura. Six children on a quest to save the Digital World.
The Digital World is protected by the Three Great Angels, Seraphimon, Ophanimon and Cherubimon. Now, Cherubimon has been corrupted by power. He has five Legendary Warriors to do his bidding: Grumblemon, Warrior of Earth, Steely Mercurymon, Arbormon of Wood, Watery Ranamon and Duskmon, Warrior of Darkness. Takuya, Kouji, Zoe, J.P. and Tommy must take on the identities of the other five Warriors - Flame, Light, Wind, Thunder and Ice - to save the Digital World from Cherubimon's plotting. They defeat enemy Digimon and use their data, called a fractal code, to renew the Digital World.
The five children defeat four of the enemy warriors, one by one, using the Spirits to Spirit Evolve into Digimon. Duskmon is the only Warrior left to defeat. As Kouji battles Duskmon, he sees the face of a boy, identical to himself. Duskmon is revealed as Kouichi, Kouji's twin brother, and purified to become Lowemon, true Warrior of Darkness.
Together, the children defeat Cherubimon, who returns to his original benevolent state. Now a new enemy arises. The Royal Knights, Crusadermon and Dynasmon, have returned. Their quest: to destroy the Digital World and collect the data, so that their ruler Lucemon may rise again. Lucemon tries to defeat the Digidestined children, and scans Kouichi's data. As Kouji remembers his twin brother, he is filled with a rage so strong that he and Takuya combine to form the supremely strong Digimon Susanoomon. Susanoomon destroys and scans Lucemon, but only manages to scan the good data. The evil data returns as Lucemon Satan Mode. Now, all five children use the Spirits to combine into Susanoomon, destroying Lucemon once and for all.
As the children journey back to their homes in the real world, they are told that Kouichi is still alive. Kouji bursts into the hospital where his brother lies, and Kouichi wakes up. All the Digidestined children have learnt something from their stay in the Digital World: the meaning of friendship.