Ruby pulls out the diary that Plusle and Minun have been guarding. Ruby explains that he realized the author of the diary was the inventor of the scanner, and since the scanner was made to detect the Blue and Red Jewels, Ruby thought the diary was probably important. Reading it, he found that the Jewels need "controllers" (or hosts) to maximize their power. The diary said that the Jewels can even choose their controllers.
Ruby goes on to point out that though Juan had said that he and Sapphire had succeeded in using the Meteorite to force the Jewels out of Archie and Maxie, he hadn't said anything about what happened to the Jewels afterwards. Ruby suggests that since he and Sapphire were nearby, the Jewels chose them as controllers and were absorbed into their bodies.
Ruby looks down at the back of his hand, where the symbol of Groudon has appeared.
Juan applauds, congratulating Ruby on his sound thinking. With this knowledge in mind, Juan asks Ruby to guess what the purpose of the mind challenge is. Juan has Ruby concentrate on ejecting the Jewel, with his Pokémon's help. Ruby succeeds, though the effort makes his hat go crooked, revealing dark bangs underneath.
Juan congratulates him again and tells him that controlling the Jewels—so that they may stop Kyogre and Groudon—is the true purpose of this training. Juan goes on to say that though Ruby had deduced the Jewels had chosen him and Sapphire because they were nearby, they may have chosen Ruby and Sapphire because they were the best choices—after all, Steven, Wallace, and Winona were all nearby.
Juan and Ruby part ways. Ruby climbs up the tree to where Sapphire—seemingly—slumbers. When he speaks, Sapphire sheepishly sits up and admits to eavesdropping. Sapphire suddenly stops responding as Ruby talks, and when he looks at her, she is leaning forward, staring in fascination at the black bangs loose of his hat. Embarrassed, Ruby hastily yanks his hat down fully again.
They resume their training and fully master ejecting and absorbing the Jewels.
Time in Mirage Island synchronizes with real time, but before they leave, Sapphire has something to tell Ruby…