Dungeon Explorer II is a continuation of the story told in Dungeon Explorer. After the fall of the Darklord Natas, Orb of Oras was once again in the hands of the good people of Oddesia. It prevented evil from entering Oddeasia for a century, thus, peace was restored. Now the evil once again threatens the world. Fades, as he calls himself, faithful to Natas, enters the throne of King Oddesia and demands the relinquishment of the Orb. With King Earl II dead and the Orb in the hands of evil, Oddesia was once again in grave danger.
At the same time, Princess Miriam of Solis was visiting Ardeen and was taken hostage by Mynos the Man-Bull. As the game supports five players, the hero who enters the throne room of Ardeen is one or more of the five to-be Immortals, with a character class of the players' choice: Fighter, Thief, Wizard, Cleric, Bard, Hunter, Dwarf or the Elf.
Dungeon Explorer II plays very similarly to its predecessor. Characters move around and talk to people in a regular RPG fashion. Since the movement is not limited to squares and it is possible to move diagonally, the game has very action-oriented gameplay. Combat is similar to that of The Legend of Zelda or Gauntlet, from a top-town view. Enemies spawn from generators and drop usable items, power-ups and provide experience as player-controlled characters kill them. Items are used in real-time and leveling up gives the characters more health.
The game takes full advantage of the CD format. It includes full voice-acted dialogue instead of common subtitled dialogue. The game also includes fully digitalized music tracks, played from the game CD, as well as hand-drawn animated cutscenes in TurboGrafx-CD fashion.