Patch a decade-old game binary to unlock a restriction

A modder wanted to lift a limit in a 2013 game on which characters could go into which playset. The game file had no source code, no symbols, and no notes from anyone else. They used Ghidra, a reverse-engineering tool, along with Claude Code set to think hard. Claude mapped what called the limit check and found it wasn't one check but 13, spread over six parts of the code. That's why earlier one-patch tries failed. After a few wrong guesses, Claude found the exact bytes to change. The result was 17 byte patches and 3 edited data files, shipped as a free open-source mod that installs in two minutes. It all took less than a day.