Ash's Cyndaquil was recalled from Oak's laboratory for the Sinnoh League but Team Rocket stole its Poké ball during the transfer. Pikachu shocked Team Rocket to get the Poké balls back but it sent them flying into the air. Ash recovered them but they were empty. Cyndaquil was the final Pokémon he located after recovering the Poké balls but it was cornered by Team Rocket's mecha. During the battle with the mecha as it was about to be captured, it evolved into Quilava and was able to destroy the mecha.