>Play pokemon
>Turn off music
>open youtube
>Search for other games music
>Play specific musics for specific event. Manually.

I'm 100% sure that some of you does this.

"Beginning of The End" for Aether Paradise invasion.
https://www.youtube.com/watch?v=6229SSjsp4o

"Divine Powers Encounter" for Faba, Lusamine, Wicke.
https://www.youtube.com/watch?v=lSznwuxG6d4

"Divine Powers Battle" for Faba and Guzma in Aether Paradise
https://www.youtube.com/watch?v=-EtFEfnwCxc

"Divine Powers Decisive Battle" for Lusamine.
https://www.youtube.com/watch?v=QW56IVU-mXw

"Megami tensei 3 Nocturne Maniax Lucifer battle" for Nihilego-Lusamine aka Mother Beast.
https://www.youtube.com/watch?v=0pwWghrkoig

And I named Zygarde as Masakado.