An animal companion who is far smart for its own good is Kyubey from Puella Magi Madoka Magica.
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When Chopper from One Piece takes a Gum-Gum Fruit, which boosts his brain, everything changes from an ordinary reindeer to something amazing.
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Ein from Cowboy Bebop is one of the smartest animals in anime despite his inability to converse like other animal friends.
Panda has already showed his talent while still a student at Jujutsu Kaisen learning how to be a sorcerer.
When the tape covering the crescent moon on Luna's forehead is removed in Sailor Moon, she may seem to be an ordinary cat to Usagi at first.
In Dragon Ball, Korin appeared to be a typical white cat but is actually an 800-year-old master of martial arts.
Despite spending the bulk of Naruto incarcerated within a Jinchuriki, Kurama retains his intelligence.
Happy from Fairy Tail is obviously not a genius, which makes him the perfect friend for the imbecilic Natsu.
The cat demon Kirara is obviously an exception to the rule that demons in Inuyasha are dedicated.
While Akamaru may follow Kiba's example, he also is able to maintain them in sync, which needs a lot of knowledge.