Xerosic is one of the five Team Flare scientists featured in Pokémon X and Y. He stands out as the sole male scientist among the group, identifiable by his red goggles. Xerosic plays a pivotal role within Team Flare, contributing significantly to its operations. Players first encounter him in the underground levels of Lysandre Labs. During an intense battle within the hideout, he presents them with a critical choice between two buttons—one to deactivate, and the other to activate the ultimate weapon. Despite assurances from both Xerosic and Lysandre, he activates the weapon regardless of the player's selection, boasting about Team Flare's scientific triumph.
Following Team Flare's collapse, Xerosic retreats into seclusion and embarks on a personal project that catches Looker's interest. Establishing a covert lab within the Lysandre Labs complex, he places an advertisement in Lysandre Café for part-time workers, hiring the Lumiose Gang for security and recruiting Emma as his test subject. Xerosic develops the "Expansion Suit," a device capable of enhancing human abilities, including superhuman reflexes, shape-shifting capabilities, and the power to manipulate Poké Balls. After training Emma in Pokémon training and lending her his Pokémon, Xerosic proceeds to control the suit remotely while Emma remains unaware inside it. This figure, known as "Essentia," wreaks havoc across Lumiose City using various disguises and personalities programmed into the Expansion Suit.
The player and Looker eventually uncover Essentia's true identity as Emma and locate Xerosic's hidden laboratory. In response, Xerosic unleashes his creation against them repeatedly. However, Looker's genuine concern for Emma's welfare prompts Xerosic to reconsider his actions, leading him to release Emma from his control. Acknowledging the success of his invention but realizing the futility of his plans, Xerosic surrenders to Looker and faces trial. Before departing, he generously donates all his Pokémon and the deactivated Expansion Suit to Emma, urging her to use them to safeguard Lumiose City's peace.
