>>533797513
I dont know what a ch4 is, but my favorite chapter 4 soundtrack?
Either "Ever Higher", because of how much it reminds me of ye olde games, or "The place where it rained", because I like Halo 3 ODST's OST too, where its...some sort of groovy jazz music in the rain, with some chill tones and yet somehow melancholic?
"The distance between two" is also up there.

Feels like tricky tony finds new instruments to fuck around with and uses them for the chapters. Not that I mind, it is rather thematic.