The Search for the Legend - S1.E22

Richie is on the S.S. Anne when a school of wild Gyarados block the waters ahead. The crew is about to take the long way around, but a grizzled Trainer named Silver orders his Salamence to send the Gyarados packing so the trip can continue. Silver also has a Chikorita, and a lifelong mission: to battle the Legendary Moltres! But Richie thinks there's something suspicious about the two researchers with Silver, especially when the ship docks at an evacuated volcanic island and Richie sees the three of them sneaking onto the shore. Richie jumps ship and follows them, convinced something is up.

When he catches them headed for the top of the volcano, they tell him Moltres should appear at this volcano tomorrow. The researchers want to sample Moltres's fire for scientific reasons, so they enlisted Silver's help—and they don't want Richie tagging along. However, Richie later overhears the researchers talking, and they're really Butch and Cassidy!