Mr. Satan shows up in the Dragon Ball Z story during the Buu Saga , first appearing in the lead-up to the World Tournament and becoming important once Majin Buu enters the plot. The official Dragon Ball site also highlights him as a major character tied to an iconic Tenkaichi Budokai moment, which matches that later-series introduction.

Where he comes in

He is not part of the early Dragon Ball or early Dragon Ball Z cast. His role becomes relevant much later, when the story shifts toward the tournament and Buu conflict.

Quick context

  • First major appearance: Buu Saga.
  • Role: comedic public hero who later matters to the main plot.
  • Early focus: tournament and fame, before he becomes more central to the Buu storyline.

If you meant a different “story” — like a specific game, movie, or fan thread — I can narrow it down.