Quoted By:
In Gen 7, after becoming Champion, a mysterious man appears in the desert, apparently suffering from amnesia. If the player shows him a Solrock/Lunatone, he will regain his memories and mention that he first encountered the Pokémon shown to him 30 years earlier, and that the "star pulses" it bestowed upon him have been passed down to "a group of wonderful men". The Pokemon you give him makes the O-Power sound after restoring his memories.
In ORAS (which by the Pokemon timeline takes place somewhere between 20 to 7+N years before Gen 7) over the course of the game some old guys will give you various O-Powers, and later when you visit them in their apartment they say are looking for someone to pass their powers to; the player tells them about the powerless man living across the hall, at which point they request that the player lead the powerless man to them. If the player does so, they will each give him their power (disappearing after doing so), turning the powerless man into Mr. Bonding. Mr. Bonding will give the player the final O-Power, Hatching Power, and leave.
This is more lore and characterization than Diantha has gotten over the course of the entire franchise.
