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The Squirtle Squad (Japanese: ゼニガメ団 Zenigame Squad) is a group of Squirtle who were abandoned by their Trainers, they are easily identifiable by the fact that they all wear sunglasses. They are all voiced by Eric Stuart in English.
Their first appearance was Here Comes the Squirtle Squad. They used to run wild in a small town in Kanto stealing things, writing graffiti and causing trouble for travellers in the area. Once they were tricked by Meowth of Team Rocket, who made a deal for them to help himself, Jessie and James capture Ash's Pikachu. When going after Pikachu it sustained a nasty injury from a Goldeen. In order to help Pikachu recover, Ash convinced the Squirtle Squad to let him free to get a Super Potion, but if he didn't return by noon the next day, they would kill Misty (in the dub, they threatened to dye her hair purple). Once Ash got back Team Rocket had arrived and decided to bomb the Squirtle Squad, causing a forest fire. Everyone went to find cover in the Squirtle Squad's cave. However, the leader of the Squirtle Squad was stuck on his back so Ash went back to help him. Working together with Ash, the Squirtle Squad defeated Team Rocket and put out the fire and were given the title of town Fire Fighters by Officer Jenny. However, the leader of the Squirtle Squad decided that it would rather travel with Ash. Ash's newly-acquired Squirtle wanted to repay Ash for saving its life by joining Ash.
The Squirtle Squad was reunited with its leader at a later point in time when they entered a firefighting competition in Johto, where they had to go up against Team Wartortle, who Ash's Squirtle had encountered in the Orange Islands. Ash's Squirtle decided to rejoin the Squad and has been with them ever since with the exception of the Silver Conference and the final battle with Brandon.
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For more information on this Pokémon's species, see Squirtle.