m8rix_ is a debugger for NES Maker games that runs alongside Mesen and lets you look at what the game is doing internally while it plays.
You can inspect live variables, change values on the fly without rebuilding, track game state, and follow what changes during gameplay, which is handy for chasing down bugs or testing ideas like what happens with 99 lives. It was built with Codex using OpenAI GPT-6.1 Sol.
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