When Misty first returned to Cerulean City, Gyarados was attacking the trainers who were looking after the Gym for Misty's sisters while they were away. Gyarados was in a such a rage it wouldn't return to its Poké Ball, forcing Misty to lock it in a cage for its safety and others, upsetting it more. During Misty's battle with the Invincible Pokémon Brothers over ownership of the gym, Gyarados watched as the 3v1 battle beginned with each of the brother's possessing their own Tentacruel. Gyarados grew concerned for Misty's Corsola during its battle, but when Misty used her body as a shield to protect Gyarados from the Tentacruel's attack, it broke free of its cage and defeated the brothers and their Pokémon itself with a Hyper Beam and Hydro Pump.
|Hydro Pump +||Cerulean Blues|
|Hyper Beam||Cerulean Blues|
|Flamethrower +||A Togepi Mirage!|
|+ indicates this Pokémon used this move recently.*|
- indicates this Pokémon normally can't use this move.
Unshō Ishizuka (Japanese and English)