StarCraft 1.16.1 and older had a buffer overflow bug in the map parsing code. The hackers in South Korea leveraged the buffer overflow to create mods for the game. The mods became so popular that if we fix the buffer overflows we kill all the mods. This talk shares the technical difficulties faced while solving this problem and also illustrates the various reverse engineering techniques used along the way: How I approached the problem and how the reverse engineering efforts helped solving them How I developed the tracers and instrumentation tools needed for the job How the emulator was designed