Pierre Rochard, also known as Steven Stone, holds the title of Pokémon League Champion for the Hoenn region. He is the son of the president of Rustboro City's prominent Devon Corporation. His deep fascination lies with gemology and researching rare stones connected to Pokémon and Mega Evolution, a passion that sometimes draws him away from his Champion duties to explore remote locations. He specializes in commanding Steel-type Pokémon, with Mega Metagross as his signature partner, capable of Mega Evolution via the Keystone embedded in his Mega Pendant. During the Mega Evolution Specials, Rochard partners with Lysandre to investigate the full potential of Mega Evolution, focusing their joint research on a powerful artifact called the Giant Rock. While exploring Hoenn, he encounters Alain, a Trainer from Kalos, and battles him using Mega Metagross. Though Lysandre interrupts the fight, the encounter fosters mutual respect between Rochard and Alain. Activating their Keystones near the Giant Rock attracts Primal Groudon and Primal Kyogre, prompting Rochard and Alain to unite against these ancient threats, combining Mega Metagross and Mega Charizard X to defend Hoenn. Later, Rochard monitors the event's aftermath from Devon Corporation headquarters before traveling to Kalos to assist Alain. Detecting abnormal energy readings from the Giant Rock at Lysandre Labs, he investigates and discovers it has mutated after absorbing energy from Zygarde, threatening Kalos. When Team Flare rises, Rochard aids in evacuating civilians and battles Flare scientists. He deduces the Giant Rock's connection to Zygarde's energy and joins a coalition of Champions to subdue it. He and Mega Metagross create a diversion enabling Alain and Ash to reach the rock's core, contributing to its neutralization. Beyond the Specials, Rochard appears in other Pokémon anime seasons. He first assists Ash and friends in Granite Cave, pacifying wild Aron and defeating Team Rocket. He later becomes a recurring mentor, gifting a Keystone to Sawyer and collaborating with him to investigate the ruins of Lysandre Labs. He also competes in the World Coronation Series, ranking within the Masters Eight and battling Ash with his Mega Metagross. His character exhibits a calm, analytical approach during battles and a strong sense of responsibility. Publicly, he is approachable and supportive of other Trainers, though his affluent background occasionally surfaces in displays of privilege. His expertise in minerals and Mega Evolution makes him a valued ally during crises involving Legendary Pokémon or ancient artifacts. He maintains rivalries with figures like Wallace and interacts with Trainers such as Alain and Sawyer, emphasizing knowledge-sharing and growth. In the Pokémon Omega Ruby and Alpha Sapphire games, Rochard guides players through key events, providing items like the Devon Scope and Dive HM. He aids in confronting Team Magma or Aqua and facilitates encounters with Legendary Pokémon like Latios or Latias. Post-game, he partners with the player in the Battle Maison, fielding teams consistently featuring Steel- and Rock-type Pokémon led by Mega Metagross. He also appears in Pokémon HeartGold and SoulSilver, distributing Hoenn starter Pokémon and facilitating trades.