Mr. Stone/Manga/PA/History/RS

Mr. Stone was first seen watching rescue his  from being sucked into a fountain during a trip through Petalburg Woods. After Sapphire rescued the Castform and healed it up, three members of Team Aqua attacked Mr. Stone and stole a special machine from his pockets. Sapphire chased after the villains and defeated them with Castform's help, but they escaped with the machine. The stress was too much for Mr. Stone, who soon falls into a coma, but he hands Sapphire a letter to hand to his son, Steven, before passing out. His Castform decided to travel with Gabby and Ty while its owner was still unconscious. The machine turns out to be a special component for the Submarine Explorer 1, which will allow it to dive to the depths of the ocean without being crushed by the depth's pressure. He and Steven aimed to use the Submarine Explorer 1 to seal the Seafloor Cavern, as they realized that villains are aiming to awaken and. With the component and the submarine stolen by Teams Magma and Aqua, Steven decided to use the backup plan of awakening the Legendary Pokémon, , and and use their power to prevent Groudon and Kyogre's clash from damaging Hoenn. Mr. Stone is later taken to New Mauville in order to escape the regions' flooding. As he lies unconscious, Mr. Stone begins muttering his son's name in his sleep. After meeting with Sapphire, Steven receives the letter from his father. The letter contained a piece of paper that completed a slab with instructions on how to awaken Regirock, Regice, and Registeel. With the help of Sapphire's Pokémon, Steven awakens the three Pokémon and uses them to help contain Groudon and Kyogre's power.