Ash and Goh, arriving in Sinnoh via ship, were both there for investigations in general, and they were at an event that had a village that simulated Jubilife Village from thousands of years ago. As they passed through, one of their friends, Dawn, called out to them. After some conversation, she invited them to follow her and she led them to Cynthia, who was taking part in the event as a sort of information giver since her knowledge of past Sinnoh, also known as Hisui, was extensive.

Meanwhile, Team Galactic had captured Heatran, a Legendary Pokémon capable of using intense fire/lava to its ability. After a series of events and energy overflow at Team Galactic's base, Heatran turned into this hulking monstrosity that resembled it, but it was held together by lava and molten rock. News of this version of Heatran broke out, and Ash, Goh, and Dawn abandoned the event and went to try and stop Heatran. After encountering Team Galactic admins Saturn, Mars, and Jupiter, Cynthia had to step in since Brock was also helping Ash, Goh, and Dawn.