Scenes from the opening credits...
It always annoyed me Thundarr had scenes in the opening credits that were never part of the series proper. The wizard summoning the demon was my favorite. (I've heard speculation that that wizard was Sabien, Ariel's stepfather, but don't know if that was the intent. It would have been a great addition to the canon if true.) The scene of Gemini and Ariel fighting was another. Why this was in neither of the Gemini episodes has always puzzled. Of course Thundarr's escape from the mutant slavers is not one to be discounted. I just wish the filmmakers could have given us another couple of episodes to show these scenes in their broader context with the undoubted visual wonders that would have accompanied them. Ah, well.
Carthago delenda est.