Dr. Oz functions as the scientific authority and chief strategist in the narrative. He initially employed scientific knowledge to overthrow the witch Gloomhilda's tyrannical galactic rule, securing an era of peace before the main events. When Gloomhilda regathers forces to reclaim dominion, he pivots to a strategy focused on recovering three legendary crystals—Love, Wisdom, and Courage—prophesied to grant eternal control over the Galaxy of Oz upon unification.

He orchestrates the quest for these artifacts, guiding Dorothy and her companions across multiple planets as their mentor and coordinating resistance against Gloomhilda's resurgence. The character deconstructs the traditional Wizard archetype: while Dr. Oz embodies authentic scientific prowess, his son Mosey masquerades as a mystical "Wizard" using technological illusions to preserve morale and authority, a ruse later uncovered.

A pivotal moment arises when Dr. Oz appears to perish in a spacecraft explosion, creating a leadership void. This apparent demise is subverted when he resurfaces alive. His return coincides with the crystal quest's climax, where the unified Rainbow Crystal enables him to permanently imprison Gloomhilda's mother—the true evil source—resolving the core conflict. These final actions safeguard the galaxy, cementing his legacy as a protector grounded in scientific mastery.