What they did
The poster, a musician by background, directed the development of a 16-bit style beat 'em up and action RPG in the Godot engine while Codex wrote most of the code. They came up with the mechanics, tested builds and steered Codex through combat work such as enemy behaviour, lane positioning and critical hits. Backgrounds started as the poster's own photos of Porto, turned into pixel art with Nano Banana, and Codex helped fix the perspective so the scenes fit the character's scale. Character animations came from Google Omni green-screen videos converted to sprites in Aseprite. The poster wrote the whole soundtrack.
How it went
After roughly six months there is a public playable demo on itch.io, in the browser and for Windows, and the poster pushed version 0.1.10 with combat fixes during the thread. Commenters who played it liked the art and music. One found the combat slow, with enemies walking into punches, and the poster agreed it is still basic. They also say they lost time redoing things that already worked.
Worth knowing
Codex handled code and fitting the art into the engine, not the art itself: the sprites and backgrounds came from image and video models plus manual work in Photoshop and Aseprite. Getting consistent animation across one character's moves was the hardest part. Matching backgrounds to the character's proportions took a lot of trial and error.