Pokémon: Advanced Generation · Battle Frontier arc
AG158 · Queen of the Serpentine!
熱闘バトルチューブ！VSチューブクイーン・アザミ！！
Synopsis
What happens.
Ash is eager to face the next Frontier Brain as he, Brock, and Max step outside of the Pokémon Center. However, Bonsly begins to cry uncontrollably, startling Ash, and Brock tells them it's feeding time, asking them to go ahead without him.
Synopsis adapted from Bulbapedia's AG158 entry, used under CC-BY-NC-SA 2.5.
Story arc · AG146-AG192
Battle Frontier.
Cast returns to Kanto. Ash faces seven Frontier Brains (Spencer, Tucker, Lucy, Greta, Noland, Brandon, Anabel). Defeats all of them, including legendary Brandon (Regice + Registeel + Regirock). Turns down a Frontier Brain offer.
Read the full Advanced Generation guidePokémon featured · 15
Who appears.
Linked entries open the species page on the Pokédex. Items without a sprite (alternate forms, regional variants, generic group references) fall back to a name pill.
More from this arc
Other episodes in Battle Frontier.
Episode synopsis from Bulbapedia, CC-BY-NC-SA 2.5. Editorial context (arc affiliation, cultural moments, character signatures) hand-verified May 2026. Pokémon, character names, and series titles © Nintendo, Game Freak, Creatures Inc., The Pokémon Company, OLM Inc. This is an unofficial fan reference.