Merlin

History
Royal Wizard of both King Marcus and King Arthur, Merlin was the one who helped King Arthur claim the throne of Camelot and trained Marcus to become King, and he's the one who formed the Knights of Chronos, and when it was disbanded, he formed a new team, the Warriors of Chronos. Merlin is a powerful wizard in addition of being a mentor to Johnny, as he was to Marcus and Arthur.

In Johnny and the Warriors of Chronos, Merlin gave quests and missions to Johnny and the Warriors frequently, and he often taught Johnny about the mysteries of Chronos and the hardships of life with lessons or even lessons disguised as missions.

Merlin served as an important support character until his death in "The Death of the Wizard" story arc, in which Kryll kills him on orders given by Sinistra. After the death of Merlin, Morgan Le Fay took his role of Royal Wizard, but the irresponsibility of Morgan didn't stick well with the role of mentor, hence she never really appeared as so.