Eusine

Eusine is a recurring character in the Pokémon anime, primarily appearing in the Johto arc (Pokémon the Series: Gold and Silver). He is a passionate researcher and self-proclaimed expert on legendary Pokémon, with an intense obsession for Suicune, one of the Legendary Beasts, whom he has been chasing for years in hopes of encountering and capturing it.

In his main appearance in the episode "For Ho-Oh the Bells Toll!" (EP227), Eusine is portrayed as bold, proud, and somewhat arrogant, showing jealousy and disbelief when Ash mentions having seen Suicune before him. He challenges Ash to a battle and attempts to capture Suicune himself when it appears, driven partly by ego. He is friends with Gym Leader Morty and uses an Alakazam in battle.

He also appears (renamed Eugene in the English dub) in the special "The Legend of Thunder!" (part of Pokémon Chronicles), where he assists young trainers against Team Rocket agents targeting Raikou. Here, he comes across as calmer, more mature, and mentor-like, though he still shows his dramatic flair (e.g., protectiveness over his cape).

Overall, Eusine is depicted as a flamboyant, cape-wearing mystic with a theatrical personality, deeply fascinated by Johto's legends.