I made a guitar hero game for game boy. It is a little broken and there is only 1 song, a slow version of Iron Man by Black Sabbath.

Directional keys to play the guitar.

Alt to enter the game.

Made with GB studio.

Status	Prototype
Platforms	HTML5
Rating	Rated 4.0 out of 5 stars (1 total ratings)
Author	Loïs Lajarretie
Genre	Rhythm
Tags	8-Bit, Game Boy, guitar-her, Music

Download

GuitarGB ROM.gb 128 kB

Install instructions

I didn't try on the Gameboy, but you can put it on a cartridge and play it. Not sure it will be easier though...

Ha! I had this same concept. I appreciate the experimentation!