Fate/Grand Order - Digimon

In the Digital World and the human realm, OmegaMon become one we he partner, also known as Yagami Kazuma, emerged victorious in a battle that determined the survival of both worlds. However, he sacrificed his life after that battle, having pushed his abilities beyond their limits as OmegaMon.

Yet, just as he was about to completely fade away, Homostasis informed him of a crisis in another world. Unable to overlook the peril facing that world, Kazuma chose to fight once again, and his fading soul was reconstructed, reborn as OmegaMon.

In the newly reborn world, he becomes the partner Digimon of Fujimaru Ritsuka, the master of Chaldea, who is engaged in the battle for humanity's restoration. Together, they embark on a new fight.

This is the story of Fujimaru Ritsuka, the last master of Chaldea, and his Demi-Servant junior Mash Kyrielight, along with the former human Holy Knight, OmegaMon, as they join hands with Heroic Spirits and work together to reclaim the future.