Worst Hero And Villain War Ever
Pyron was originally created by Malmoth to destroy invaders from Netherrealm. He ended up becoming one of the most powerful and smartest beings in the Universe, and it ultimately was up to Raiden to defeat Pyron. After a long fight, Raiden sealed him in the Earth's Sun.
Several hundred years later, Malmoth commanded The Gatekeeper to release him alongside LeChuck so he could set Ragnarok into motion. The Gatekeeper did as he pleased and Pyron ended up ascending from his Sun prison.