Katsu

Katsu was the son of Shiba Katsuda and Soshi Jomyako, the Dark Oracle of Air.

Fighting the Taint
Katsu was raised by his father alone, who never gave up to the Taint, while his mother did. During his childhood, Katsu roamed with him in the Twilight Mountains and the northern Shadowlands, fighting against their own corruption. When his father finally died, Katsu used the Dark Covenant of Earth to summon Yasuki Nokatsu, the Dark Oracle of Earth. Katsu used his wish to rebuild the Sunset Tower, loved by his father during his service as an Imperial Guardsman. Afterwards, Nokatsu took him to serve Daigotsu.

Refugees
Though Katsu was forced to swear fealty to the Dark Lord, he never lost his honor and his desire to not fall to the Taint. Even when he would be very loyal to Daigotsu, Katsu managed to contact a samurai called Daidoji Gudeta to ask the Crane Clan to receive refugees of the Shadowlands that, just like him, wouldn't be willing to submit their minds to the Taint. The first of this refugees was the monk Komaro.

However, Daigotsu always kept Katsu by his side as one of his henchmen.

Becoming a Khadi
Eventually, Daigotsu became aware of Katsu's activities so he took him in his travel to the Burning Sands. There, Daigotsu turned him into a khadi, the same kind of heartless sorcerer that Iuchiban was, so he could understand better his enemy and control Katsu effectively.

Spider Clan
Katsu joined the Spider Clan on its formation.

Katsu played an important role during Daigotsu's mass assasination plan in 1170, allowing the Dark Lord to communicate with all of his agents simultaneously.