The interesting part of this project isn’t the editor — it’s what runs inside it. The tool modifies tracks, AI, sprites and physics in the original Super Mario Kart and exports a ROM that plays on real SNES hardware, with the user supplying their own copy of the game so nothing is stored. Underneath sits a near 1:1 recreation of the game running natively in GDScript, with C++ helpers for the sound engine.

The method was to start from a disassembly:

  • Point the agent at a disassembly found online, then have it run its own disassembler to fill in whatever was missing or misunderstood
  • Because the result is a normal Godot project, modern techniques apply directly — raise the walls, swap the kart, lift the physics, one click each
  • Aseprite edits were done by instructing the agent to write scripts that Aseprite runs, not by driving the paint tools
  • Cost: about a week of tokens on a Pro-tier subscription; four days start to finish, mostly hands-off in autonomous “goal mode”

For weaker models or tighter budgets, the advice is to stop chasing cycle accuracy:

  • Tell the agent to replicate behavior using the assets from the supplied ROM — much faster to something playable
  • Have it build the verification loop: run it against an emulator, compare frame by frame
  • The author’s read on difficulty: 8-bit and 16-bit era games are, for current models, trivial

Other devs in the thread report the same pipeline elsewhere — a native widescreen fix and Xbox controller support for KOTOR from two prompts, a Phantasy Star IV port in progress, a Batman NES disassembly that worked out the data structures and started implementing logic on its own. The recurring insight is that disassembly tooling was already one-click; the hard part was always comparing, labeling and documenting the data and the functions, and that is exactly the part an LLM with an emulator to check against does cheaply.

The caveat is legal rather than technical. The author isn’t releasing the recreation despite believing it is technically legal, and the editor is designed so it always requires the user’s own ROM and never stores any of the ripped graphics. The thread’s running joke is that Nintendo is the one who will get it shut down.