Battle Spirits: Shounen Toppa Bashin

Battle Spirits: Shounen Toppa Bashin is an anime series that aired from 2008 to 2009 as the first series of the Battle Spirits franchise.

The story follows Toppa Bashin, a young boy who aims to be the best at the card game "Battle Spirits" alongside his friends. Possessing a mysterious red pendant from his father, one day Toppa meets J Sawaragi, the prodigy champion at Battle Spirits who also possesses a similar pendant. After agreeing to battle, they both find themselves teleported to the Isekai World - an arena where Spirits from the game become real. Diving headfirst into this new world, Bashin makes his way to the top to chase his dream while encountering other card battlers who also possess pendants.

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Toppa is at a swimming pool.

Episode 1
Toppa changes his clothes.