He challenged Ash to a Pokémon battle with his Golem and even though he won against Bulbasaur he forfeit when his Golem turned into a giant rolling fireball courtesy of Ash's Charmander. He admired James of Team Rocket who he referred to as "Little Jim". Later during a storm he was so touched that they would help a sick Shellder that he, Tyra and the entire gang changed their ways and even gave Ash the nickname "Awesome Ash".
Chopper used his Golem against Ash's Bulbasaur and hurted it. When Golem was ignited by Charmander's Flamethrower, it went on a rampage, so Chopper had to call it back.