Sarien is an open source, portable implementation of the Sierra On-Line Adventure Game Interpreter (AGI). It is currently under development; no production-quality packages have been released. Sarien is able to execute Sierra On-Line AGI games at different levels of playability. Leisure Suit Larry, King's Quest II and Mixed-Up Mother Gooose are some of the games that have been played from beginning to end with Sarien.
Sarien has features not present in the original Sierra On-Line interpreter. These extra functionalities include double horizontal resolution, enhanced color palette, dictionary and picture viewers, three-channel PCM sound, support to AGDS (a Russian AGI clone) games and a "Quake console" with integrated debugger.