Bunnelby was used by Clemont in his first battle against Ash and Pikachu. Bunnelby was shown to be a strong battler, easily dominating the first part of the battle until it made the mistake of clamping Pikachu's tail with its ears. Pikachu responded with an Electro Ball , which dealt Bunnelby a lot of damage. Before the battle could continue from there, Team Rocket attacked and tried to capture Pikachu and Bunnelby. Clemont had Bunnelby use Mud Shot against Wobbuffet so Pikachu could attack with Electro Ball. However, Wobbuffet managed to dodge Bunnelby's attack. After Froakie appeared and stopped Wobbuffet with its bubbles, Clemont had Bunnelby use Dig to propel Team Rocket into the air so Pikachu and Froakie could send them blasting off with Thunderbolt and Water Pulse respectively.
Citroid, also the Gym Leader Clemont built, made a deal with Clemont: If Bunnelby defeated Heliolisk, Clemont can reset the robot. When Bunnelby was utilized, it was being knocked around by Heliolisk's Bulldoze & Parabolic Charge attacks. At the end, Bunnelby won the battle with Dig and Mud Shot.