Game Console Cores
Game Boy / Game Boy Color

The Game Boy is a portable game console released by Nintendo in 1989. It was followed by the backwards compatible Game Boy Color in 1998. It is best known for making Tetris a pop culture phenomenon in the early Nineties.
https://en.wikipedia.org/wiki/Game_Boy

This Core for the MEGA65 has some minor shortcomings. As C64-Joysticks officially only have one button, you can map the Game Boy buttons A or B to Joystick Up so that you can play jump and run games as you would on a C64. All Game Boy buttons, including Start and Select can be pressed via the MEGA65 keyboard.
The Core can load ROM files for the Game Boy and Game Boy Color. It features an unlicensed BIOS that can be replaced by the user with official BIOS files.
Full instructions for this core can be found at https://tinyurl.com/gbc4mega65
Download the Core on the MEGA65 Filehost: https://files.mega65.org?id=03b68172-d6ff-49f0-971e-15bea2c6ad9a
The Core discussion on Discord: https://discord.com/channels/719326990221574164/1481279628101554208
The Core issue tracker can be found on Github: https://github.com/sy2002/gbc4mega65