I'm working on a rhythm game for original NES: https://zeta0134.itch.io/tactus
This is written entirely in 6502 assembly, and uses a fun new mapper that helps a little bit with the music, so I can have extra channels you can actually hear on an unmodded system. It's been really fun to push the hardware in unusual ways.
Currently the first Zone of the game is rather polished, and I'm doing a big giant pixel art drawing push to produce new enemies, items, and level artwork to fill out the remainder of the game. It's coming along slowly, but steadily. I'm trying to have it in "trailer ready" / "demo" state by the end of this calendar year. Just this weekend I added new chest types and the classic Mimic enemy to spice things up.
Nice! What’s the new mapper you’re using? Is it available as an IC or does it use FPGA or something?