He-Man and the Masters of the Universe (2002)

But that was not the "ultimate" defeat of the Snake Men, which saw them sealed in the Void. The elders could have turned Serpos into Snake Mountain after the formation of their council, and then the Snake Men took up residence there, until the later battle that ended with them being sealed in the Void.

I'm rather surprised this hasn't been pointed out before... but there is a major continuity error in this episode. In previous episodes, it has been mentioned that the Snake Men used to use Snake Mountain as their base. Yet in this episode, it's shown that Snake Mountain was the frozen form of Serpos, sealed away by the Counsel of Elders. The problem? The episode "The Power of Greyskull" demonstrates that there WASN'T a Counsel of Elders until AFTER Hordak had defeated the Snake Men! I think that deserves an "Oopsie!"

Isn't anyone concerned the King Hiss could free Serpos again in the near future? As far as we know, the Medallion of Serpos is still floating around somewhere. Surely the Scorceress and/or Zodac would know how Hiss freed Serpos in the first place.

Response to that thought: that is an important consideration. It leads me to believe that Serpos was not truly a divine entity, but "merely" a huge monster whom the snakemen decided to worship; either that or King Hsss was not being truthful when he claimed he was controlling it.

Somewhat strange that a god could be controlled by a wizard... shouldn't King Hiss be the one taking orders from Serpos, and not vice versa?