Dungeon Adventure concludes Level 9's Middle Earth lineage of fantasy interactive fiction games (later reprogrammed with graphics in Jewels of Darkness). The player is searching for magical treasures within the Demon Lord's fortress, after his defeat in Adventure Quest. There are over 200 specific locations, including rooms within the tower and outdoor locations to navigate en route. Objects range from a coffin and a giant belt to nasty images and a packing case; also watch out for Orcs, Dwarves and other creatures. The parser's vocabulary contains all the standard terms - EXAMINE, TAKE, OPEN and FILL for example.