Details: One of the ten possible challengers you will face as you sit on the Champion's Chair in the Champion's Hall after defeating the Elite Four is Ryuki. He is a trainer from another region, one that's also a famous musician, who specializes in Dragon Type Pokemon.
Challenger Ryuki - Level 61 Garchomp, Level 61 Drampa, Level 61 Turtonator, Level 61 Dragonite, Level 61 Kommo-o