|World of Origin||Ni No Kuni|
|Alter Ego||Galeroth Felgrimm|
|Alter Ego||Gnauss Wisden|
Sedulus Astrum was a character introduced in the Ni No Kuni Movie. He was the main antagonist of the movie, who was the crown prince of Evermore. He was the elder son of King Astrum, which make Fidelius his younger brother, and Astrid his niece. He also had two different alter egos: Galeroth Felgrimm and Gnauss Wisden.
Sedulus was born into the Evermore Royal Family, King Astrum was his father, he had a mother but she was never shown or named. Sedulus recalls his parents not caring for him and preferring Fidelius his younger brother over him. His father sent him to live in Beladon, which was the kingdom Evermore was with for some reason. He resented that fact but over time grew accustomed to life in Beladon, he even had a wife and children. Then one day his father attacked the kingdom with the Mornstar, leaving no survivors to save for he himself. This was due to using some dark form of alchemy. He crafted a new body using dark magical beasts and took the form of Gnauss Wisden. Sedulus was filled with anger and spite and so vowed revenge. No one would suspect him because all the other characters thought that he was as good as dead. He used this to his advantage and created two alter egos: Gnauss Wisden and Galeroth Felgrimm.
Throughout the story, he was able to cause a lot of damage due to these two alter egos.
He was the magic chancellor to the king.
By employing the Black Hooded Man. He was the main reason both Haru and Yu arrived in Ni No Kuni, after he was ordered to stab Kotona.