lucasartsifier

Sierra adventure games, unlike LucasArts ones, let you get stuck. Forget the sunscreen in Los Angeles, board the cruise ship, and you die days later on a raft with no way back. This tool decompiles a Sierra SCI game, abstract-interprets the scripts into a graph of guarded room transitions, item movements and plot-flag writes, and finds the states where input is still accepted but victory has quietly become impossible. It then derives guards that prevent those crossings, verifies them against the guarded model, compiles them and installs them back into the game. Nothing about any title is hardcoded: the start room, the victory room, the death signal and the debug globals are all discovered from the game's own code. Four titles have been analyzed and play-tested on the same engine with no per-game analysis, spanning Leisure Suit Larry 2 and King's Quest IV on SCI0 through King's Quest VI and Laura Bow 2 on SCI1.1.