Steven Stone/Anime/Main series/History

Steven was first mentioned by his father in Stairway to Devon who claimed he would be a good person for and  to know.

He then appeared in person in A Hole Lotta Trouble. Unlike his game counterpart, Steven was not mentioned to be or have been the Hoenn League, but was simply a powerful Trainer. Instead, Wallace is said to be the Champion later in the. Steven and his were digging in Granite Cave, looking for rare stones. As Ash, his friends, and fell down in a hole, Steven stopped with what he was doing and quickly checked out what caused a crash to occur. Steven found Max,, and in a dark part of a tunnel they were in.

They went to search for Ash and the others, who were being chased by a horde of agitated Aron. Steven had his own Aron use to calm the agitated horde. He then told the horde that the group were good people and they turn around and leave. After both sides were reunited with each other, Steven found out that Team Rocket were the ones who caused the Aron to get angry. Steven handled Team Rocket on his own by having his blast them off with with. After their defeat, Steven found a Fire Stone with the help of Aron. He decided to lead the group out of Granite Cave and took them to a deserted inlet, an ideal place for Ash to train for his rematch with Brawly. He then boarded a small boat and wished the group luck for the future. At the end of the episode, Ash vowed to train harder so one day he could be powerful enough to battle Steven.

Mega Evolution Specials
Steven reappeared in Mega Evolution Special II, where he battled Alain using his Mega, but the battle is interrupted by Lysandre. Deciding to cooperate with Alain and company, Steven traveled to their destination, a small temple with two pillars in the center. When Alain and Steven held their Key Stones to the monument, a staircase of light appeared to lead them further within the ancient ruin. There, they discovered a similar mechanism that summoned a glowing Giant Rock from underneath the ruin. After Lysandre and his research team began analyzing the giant stone, a Rayquaza appeared from the sky, Mega Evolved into Mega Rayquaza, and started wreaking havoc on the surrounding area. Alain, Steven, and their Mega Pokémon partners tried to fend off the Legendary Pokémon, but were overwhelmed.

In this series, Steven is confirmed to be the current Champion of the Hoenn League, indicating that Wallace no longer holds the title. In Mega Evolution Special III, Steven brought Alain and Mairin to the Devon Corporation headquarters to analyze the situation of the missing Giant Rock. There, they receive a conference call from Lysandre who informs them that both Groudon and Kyogre have undergone Primal Reversion and are set to collide in the middle of the ocean. Steven recalls the Primal Reversion myth, and fears that the two Pokémon clashing again could have catastrophic consequences. As a result, he and Alain depart on a plane to check on the situation from the sky, with Mairin secretly stowing away with them.

He reappeared in Mega Evolution Special IV, where he alongside Mairin and her Chespie have returned to Kalos. They contacted Professor Sycamore regarding Alain as he separated from them. Later, they arrived in Lysandre Labs with Lysandre and his secretary waiting for them. While Lysandre's secretary escorted Mairin to watch Alain battle ten Trainers, Steven discussed to Lysandre about the Giant Rock. Lysandre showed Steven the Giant Rock in another room and explained that it is kept in a high-security tank to prevent energy from leaking out, as well as bringing up the fact that the weather trio fought in Hoenn previously. Steven was then seen watching the battle between Alain and Malva. After the battle, Steven arrived to where Chespie was lying on a bed, unconscious from absorbing too much energy from an experiment.

Kalos
Steven reappeared in the main series in a flashback in Rivals: Today and Tomorrow!, in which he met with Sawyer. He also appeared in another flashback in Coming Apart at the Dreams!.

He reappeared in The Right Hero for the Right Job!, Rocking Kalos Defenses!, and Forming a More Perfect Union!, where he joined the battle against Team Flare. He eventually battled alongside Ash, Alain, Diantha, and all of Kalos's Gym Leaders in order to stop the Giant Rock.

It was revealed in The First Day of the Rest of Your Life! that Steven gave Sawyer a Key Stone. Later, in Till We Compete Again!, Steven and Sawyer were shown at the Lysandre Labs, studying the Giant Rock that was recently held there. He proceeded to give Sawyer some information, which Sawyer then wrote down in his notebook.