This is the part I lack research the most!
The original idea was to play the traditional Iranian music i.e (شجریان) playing in the Fantasy world. When player reaches the Nightmare world, it would be a Foley floating type of sound, kind of like when ear is blocked.
Point is to introduce Persian music, similar to Moon Knight introduced Arabic music.
Another great inspiration is the new prince of Persian games that did it really well.
This is a bit more upbeat, but imagine something more on the calmer side for the Normal map and cranks up the music as the player changes the worlds. Bullet Per Minute did a sound to gameplay, Ape Out did similar but this is more based on the duration, and it's on 7 seconds so every 2 beats we can have a potential point of swap.
I am not sure how it could work but throwing in ideas: what if the normal world just plays the tune, but the fantasy do the lyrics, and the lyrics is describing what the scene, essentially what player is going through, then for the nightmare more stressful notes and rhythms?
More references
Problem is, I am not that much into music (in general)
Apparently these are popular artists:
But my focus is more of a instrument than anything else, then again, traditional musicians voice was part of their instrument, i.e. that Shajarian that I mentioned earlier:
But I am unsure on how I can make music stylised, more than the basic ways, so I am open to suggestions. I do believe it should closely connect with UI / UX Design, so please read that segment too as it goes further in detail in terms of Feel and UX aspect of the game and the intentions behind the choices.
Also to note: We really don't want this to be a typical Mideastern music, in deserts!
At it's core, this game is meant to introduce Persian culture!
"Vertical Layering":
Normal: A solo, lonely Setar melody.
Fantasy: The same melody, but with lush, heroic strings and a Daaf (drum).
Nightmare: The same melody, but distorted, played on a Ney (flute) that sounds like it's screaming, with heavy, metallic industrial echoes?