In its debut appearance after evolving into a Magikarp, Gyarados was seen as an ill-tempered Pokemon with uncontrollable rage similar to James' Gyarados from the episode, Pokemon Shipwreck!. It was demonstrated when he was out of control, such as scaring Misty's other Water Pokemon beneath the pool, and like Ash's Charizard, he hits Misty several times with Hydro Pump, just like how Charizard hits Ash's face from its Flamethrower, and Misty did her best to tame it despite her fear of it as a child. When Misty risks her life for her Corsola and Gyarados itself from the Invincible Brothers' Tentacruel's attack, Gyarados became concerned by Misty's sacrifice and begins to obey her by breaking the cage and defeating the brothers with its powerful abilities. Gyarados became happy when Misty was safe and finally obeys her when she needs it in battle as seen in A Togepi Mirage! where it was released by Misty to battle Hansen's Shedinja, and to surprise Ash from its appearance, not to mention having learned Flamethrower itself to break through Shedinja's Wonder Guard ability that rendered all attacks but its weaknesses ineffective on it.
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.
In A Togepi Mirage!, Gyarados was released by Misty to battle against Colonel Hansen and his Shedinja to surprise Ash and the group as Togepi who is now evolved into a Togetic protects five of the Togepi from Shedinja's Solar Beam using Safeguard. Gyarados quickly defeats Shedinja by its newly learned Flamethrower as Hansen's left mustache and brow are burned due to its effects and was arrested for treason by Sara's royal parents.
|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)