In Heir to the Stars: Joker, Lionel Kingsleigh appears after Joker had released himself, becoming fully omnipotent, omnipresent, and omniscient. Buddha appeared, who 'willed' himself into the same state as Joker. This caused Lionel Kingsleigh to step on to the battlefield in order for the two to truly witness Top Tier power.
In Heir to the Stars II, he is the one that wrote the story.
Powers and Abilities
Author Authority: By his word, he is able to strip two all-powerful beings of their absolute all-governing status. In fact, all systems of the story had been changed so that neither of them were ever Supreme. He also stripped them of their Omniscient and Omnipresent status.