A Question About Custom Music

[Fortnight]

So, I know that making a new battle_westeros2.ogg file and overwrite the previous one will change the music, but what if I extend the list, with a westeros8 file and further?
And I've also noticed some old music files for native faction encounters, are those used in any way or can I get rid of them?
And is it possible to have different music for different AWOIAF faction encounters?

[Produno]

The only native music left is victory.wav.

You should be able to add more music by adding them to music.txt file.