There’s a CHIP-8 emulator written for most platforms, now including UEFI. The executable uc8.efi is built using the GNU-EFI toolchain, not the Tianocore toolchain.

“CHIP-8 emulator as an UEFI application”

Usage: uc8 FILE [ROM]

Follow the instructions on your screen. In case of trouble, press Z.

About CHIP-8, Wikipedia says: ”
There are a number of classic video games ported to CHIP-8, such as Pong, Space Invaders, Tetris, and Pac-Man. There’s also a random maze generator available. These programs are reportedly placed in the public domain, and can be easily found on the Internet.”

https://github.com/Reisse/uefi-chip8

https://en.wikipedia.org/wiki/CHIP-8