In the anime episode "For Ho-Oh the Bells Toll!", Eusine comes across as a proud and somewhat arrogant individual, displaying a near-religious devotion to Suicune. His behavior hints at a superiority complex, especially when he challenges Ash for claiming to have encountered the legendary Pokémon. This reaction might stem from jealousy, considering Ash has also seen Ho-Oh, while Eusine hasn't met any legendary creatures himself. In the same episode, when Eusine finally sees Suicune, he attempts to capture it partly for personal glory, ironically making him no different from those he deems unworthy. This contrasts with his role in "The Legend of Thunder!" where he only briefly mentions Suicune in reference to other legendary beasts.
In "The Legend of Thunder!", Eusine assists Jimmy, Marina, and Vincent in their fight against Attila and Hun. Marina develops feelings for him due to his cape. He shares a close friendship with Morty, an expert on Ecruteak's legends. Morty often tries to reason with Eusine, urging him to calm down, but to no avail. When Eusine leaves abruptly at the end of the episode, Morty's lack of surprise suggests this is a recurring pattern.
In the Pokémon Adventures manga, Eusine is quite the showman, particularly around women, performing flashy magic tricks and even giving out autographed pictures. He travels on a Jumpluff. He seems to be good friends with Morty, who helps him search for Suicune.
Eusine is first mentioned by Morty, who says Eusine asked him to use his powers to find Suicune, without success. After Morty is defeated by Suicune, he contacts Eusine, prompting him to pursue the creature himself. During his hunt, Eusine encounters Crystal, who accidentally shocks Arckee with his Electrode. Eusine declares them rivals before disappearing. Later, he visits an elderly couple and tricks them into giving him Moomoo Milk by pretending to cure their Miltank. However, Crystal follows him and discovers that Eusine actually used a berry to manipulate the situation. Eusine doesn’t seem to care about deceiving the couple. They then encounter what appears to be Suicune, but it turns out to be a Ditto sent by Team Rocket as a distraction. Eusine and Crystal manage to let the real Suicune escape and defeat the Team Rocket Elite Trio.
