Super Buu is a major villain in Dragon Ball Z, formed when Majin Buu absorbs other beings and becomes a more intelligent, ruthless, and dangerous version of himself. He appears near the end of the series as one of the final antagonists, threatening Earth and the universe with immense power, regeneration, and unpredictability. Super Buu serves as a key obstacle for the heroes, forcing them to rely on teamwork, transformations, and ultimately fusion to stop him.