Little is known about the history of the Magus or the rest of the residents of Castle Wyvern. The Magus was originally the Archmage's apprentice but became the court magician of Castle Wyvern following the Archmage's banishment. When the Archmage returned and poisoned Prince Malcolm, the young Magus was given the task of finding a cure but announced that he could only do so if he had the Archmage's Grimorum Arcanorum. Three gargoyles who would later be named Hudson, Goliath, and Demona, managed to track down and defeat the Archmage and retrieve the Grimorum so that the Magus could cure Malcolm's poisoning.
The Magus was Princess Katharine's adviser during her reign over Wyvern and shared her dislike for the gargoyles. When the Captain of the Guard and Demona betrayed the castle to the Vikings led by Hakon, causing the destruction of the Wyvern Clan, the Magus, the princess, and refugees within the castle walls were taken, hostage. It was the grief-stricken Magus that cast the spell that imprisoned the remaining members of Goliath's clan in stone believing that the gargoyles were responsible for Katharine's supposed death. However, upon learning of Katherine's survival, he became ashamed of his actions and felt tremendous guilt and finally came to realize the error of his prejudiced ways against the gargoyles. However, before he and Princess Katherine left, Magus froze Goliath at his request and felt compelled to protect the rookery eggs as a way of making up for his actions and wrong views against the gargoyles.
He used his magic to guide Princess Katharine and the eggs to Avalon, giving up his spellbook of the chance to join them and help raise the hatchlings. Though he loved Princess Katharine greatly, he felt that he had little to offer her without his magic, and watched sadly as the love between Katharine and Tom grew stronger.
When the Magus' former master, the Archmage, returned and attacked Avalon, the Magus helped Elisa Maza awaken the sleeping king from his enchanted sleep so that he could aid in the battle. By tapping into Avalon's magic, the Magus was able to defeat the Weird Sisters in the Hollow Hill, but using too much magic without anything to channel it through ultimately cost him his life. He was laid to rest forever in the exact spot where King Arthur was awoken from with Katherine at his side, saying that he would never leave her.
- Magus is Latin for "wizard".
- The Magus' real name is not known.
- It is remotely possible that the Magus was either the son or relative of the Archmage, given that they both had the same hair color, magical ability and use of the Grimorum. This theory cannot be proven based on any episodes or comics.