Gary's Blastoise (Japanese: シゲルのカメックス Shigeru's Kamex) was the first Pokémon obtained by Gary Oak on his journey as a Pokémon Trainer. Its Japanese voice actor is Unshō Ishizuka and his English voice actor is Eric Stuart.
Blastoise first appeared in a flashback as a Squirtle in Challenge of the Samurai, though the episode did not reveal which of the three Trainers who left before Ash owned it. Finally, in The Ties That Bind, the fully-evolved Blastoise was revealed to Ash when Gary sent it out to battle Heracross.
Blastoise is Gary's strongest Pokémon. It took out Ash's Heracross and Bayleef, and it nearly defeated his Muk. It also put up a good fight against his Charizard, but in the end, Ash defeated his rival by having Charizard heat up the field around Blastoise when it was firing Hydro Pumps at it; when Blastoise attempted to cool the field down, Charizard took advantage of the resulting steam to get in close to Blastoise, subsequently defeating Blastoise with its trademark Seismic Toss attack.
Gary and Blastoise later appeared in Ill-Will Hunting! where they helped Ash, Brock and Dawn in protecting the Shieldon from the notorious Pokémon Hunter J and her evil minions.