High Quality Content by WIKIPEDIA articles! The Dungeon Master`s Guide (DMG or DM`s Guide; in earlier editions, the Dungeon Masters Guide or Dungeon Master Guide) is a book of rules for the fantasy role-playing game Dungeons Dragons. The Dungeon Master`s Guide contains rules concerning the arbitration and administration of a game, and is intended for use primarily or only by the game`s Dungeon Master. The original Dungeon Master`s Guide was published in 1979, and gave Dungeon Masters everything they needed to run a D D game campaign.