map of the fictional realm of Ancardia, and would have the player complete various quests in those dungeons to progress the game. A major feature was the influence of Chaos forces through unsealed portals, which the player would have to close. While in areas affected by Chaos, the player's character would become tainted, causing mutations that could be either detrimental or beneficial. ADOM, like NetHack and Angband, would gain a devteam to maintain the code and implement updates and patches to avoid excessive forking. Other variants Not all early roguelikes were readily classified as Hack or Moria descendants. Larn (1986), developed by Noah Morgan, borrowed concepts from both Hack (in that there are persistent and fixed levels) and Moria (in the availability of a shop level and general difficulty increasing with dungeon level), but while these two games have spiraled in size to take multiple play sessions to complete, Larn was aimed to be completed in a single session. Larn also uses a fixed-time feature, in that the player had only so many turns to complete a goal, though there were ways to jump back in time as to extend play. Omega, developed by the Laurence Brothers in the late 1980s, is credited with introducing an overworld concept to the roguelike genre, prior to the feature's appearance in ADOM. Omega was often remembered for its odd inventory approach in which the player would have to pick up an object, considering it being held, and then moving that object to a bag or an equipment slot. Linley's Dungeon Crawl (1995) was created by Linley Henzell and featured a skill-based character progression system, in which experience points could be used to improve specific skills, such as weapon proficiency or trap detection. One fork of this would form the basis for Dungeon Crawl Stone Soup (2006). SSI's Dungeon Hack (1993) offered randomized dungeons and permadeath within AD&D 2nd Edition rules. Mystery Dungeon games (1993–onward) Through 1993, roguelikes primarily existed in computer space, and no home console variants had yet existed. Two of the earliest-known attempts were Sega's Fatal Labyrinth (1990) and Dragon Crystal (1990), but which lacked the depth of a typical computer-based roguelike. Neither proved to be successful games. Chunsoft had gained success by developing the Dragon Quest series, a series which established fundamental aspects of the computer role-playing game genre, popular for Western computer audiences, into a more streamlined approach better