Steven Stone (Daigo Tsuwabuki in the Japanese version of Pokemon) is the Elite Champion in Pokemon Ruby and Sapphire, and a powerful wandering Trainer in Emerald, having relegated his title to Wallace. He is a master of the Steel-type, with a Metagross being the cornerstone of his team.

Steven is the son of the president of the Devon Corporation, and he and his father both collect rare stones. Steven makes his home on Mossdeep, and when the Elite Four are beaten in Pokemon Ruby, Sapphire, and Emerald, he will have left a Beldum and a note for the player.

In the anime

Steven's only appearance in the Pokemon anime was in A Hole Lotta Trouble. He helped Ash, his friends, and Team Rocket escape from an underground cavern.

At the end of the episode, Ash vowed to train harder so one day he could be powerful enough to battle Steven.

In Pokemon Adventures

Steven met Ruby while looking through the Granite Cave. During a battle with wild Mawile, Ruby's Skitty bumped into one of Steven's Moon Stones, causing it to evolve.

Steven was well-aware of the danger Team Magma and Team Aqua presented, and extended an invitation to Ruby to join the fight against them. Steven invited him to help, but Ruby declined because he didn't like battling. The armlets on Steven's arms are devices he can chip away stone with, to grab and retrieve rocks he sees that are out of reach.

Later in the series, Steven confessed that he and his father, the owner of the Devon Corporation, knew about the schemes of Team Magma and Team Aqua quite long ago. Mr. Stone built the Submarine Explorer 1 so that Steven can seal the Seafloor Cavern and no one would be able to wake Kyogre and Groudon. The backup plan in case it fails would be to unseal Regirock, Regice, and Registeel.

Steven later assembles the rest of the Hoenn Elite Four in order to fight against Kyogre and Groudon. With the help of Sapphire's Wailord and Relicanth, Steven and the Elite Four unsealed the Regis. Steven took control of Registeel and gave the other two Regis to the other members of the Elite Four.

Knowing he would die in Kyogre and Groudon's battle, Steven stepped down from the position of Champion, and gave it back to Wallace, who was actually the true Champion while Steven had only been a runner-up. After Kyogre and Groudon returned to their respective domains, Steven apparently died from the strain of controlling the Regis, but was later revived under mysterious circumstances when Ruby released his Celebi.

Steven later traveled to Sinnoh to collect the rare stones found in the region. He had purchased a Villa but sold it to Platinum and returned to Hoenn at the start of the Platinum chapter.

Steven uses his Metagross to fly around Hoenn. Its magnetism allows him to float atop it.