Trio

Zeus was Trio's starter, who he acquired through illegal means. As Trio was not able to become a Trainer due to Johto's strict and unfairly biased laws, his only option was to steal an unlocked starter Pokeball and use that as his ticket to obtain a license. And while Trio initially only viewed Zeus as such, over time the gator Pokemon and his cheerful personality grew on him.

For his part, the water Pokemon has been completely faithful and dedicated to his Trainer since day one, when the pair spent a night in the dangerous woods, and Trio protected his weak and underleveled starter from a pack of wild Raticate. Zeus fought hard and earned several scars during their climb through both regions' gyms, deadly serious in each battle, but never lost his puppy-like demeanor.

One of the first Pokemon Trio caught, Hera didn't entirely get off on the right foot with Trio, as she was protecting her scrap of territory when battled and caught. Over time, however, her nature as a Growlithe leaned into her becoming loyal to Trio, especially as his commands and instructions allowed her to win and survive every to-the-death fight she was put into.

Late in their Johto travels, the team would encounter Ho-Oh, the legendary fire phoenix Pokemon, who turned his flames on Trio. Hera defended Trio from the attacks, putting her loyalty to the test, and solidifying her dedication to him. She is fairly expressionless and doesn't show affection easily, but is visibly relaxed whenever she is around her Trainer.

In stark contrast to Hera's calm exterior, Eris is bouncy and energetic and struggles to become serious, even during battles. Trio obtained them as an Eevee after doing a favor for Bill, and evolved them as a Jolteon due to his difficulty in obtaining an electric-type Pokemon during his travels. Eris was all too happy to continue receiving attention and affection, and rarely seemed to understand the severity of the life-and-death battles they raced into.

Eager to please their Trainer and receive even the slightest returns of approval and praise, Eris' eagerness proved enough to allow them to succeed against the Elite Four twice. When Trio left the regions and released or re-homed his unused Pokemon, he wanted to rehome Eris- who was much more suited to a loving home than a life of battles- but couldn't, as he still needed them to balance out his team.

The first Pokemon Trio caught since having left Johto, Atlas first encountered Trio by stealing his jacket, which had a sandwich in the pockets, and running off with it. After pursuing him to get his jacket back, only to see that the mischevious Riolu had stolen it simply because he was hungry, Trio made the choice to catch him so that he wouldn't endanger himself by stealing again, or go hungry.

Since then, Atlas practically idolized Trio, and quickly evolved into a Lucario after his first Gym battle. His new ability of telepathy certainly shocked his Trainer, but the pair eventually became used to it and used their newfound communication to clear up some misunderstandings about their Pokemon-Trainer relationship.

Initially caught as a Haunter by Trio's friend and doubles partner Penny, Hades was traded to Trio as Penny wanted nothing to do with the ominous and twisted ghost-type Pokemon. Having originally named it "Bastard" after it went after a lone deerling, Penny agreed to rename him for Trio- but accidentally renamed him to "Hades, the Gengar Formerly Known as Bastard". As a result, the Gengar answers to both/either name, whichever is more convenient for it to cause trouble.

Causing trouble is its favorite thing to do, as a matter of fact- though Trio is wary of the ghost Pokemon and its motives (which become known later as its fascination with death, being able to sense just how much death Trio has seen in his days), he keeps the Pokemon on his team for its utility and strength in battle. Time will tell on which name this Pokemon ends up living up to more.