From the Introduction:
Dark Lust is the first mini-expansion for Exiles Of The Wicked Maze. As indicated in the introduction story, the events of this mini-expansion occur roughly five years after the original timeline of the game. Many of the original foes have been replaced by tougher counterparts, making this expansion more challenging than the original game.
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The Dark Lust expansion presents changes to three major components of the main game rules: the foes, the special items, and the optional rules/missions. When playing the game with the expansion, you will use all of the normal rules, charts, etc. of the main game with the exception of the Dark Lust foes and foe chart, the special items and special item chart, and the possible inclusion (if you so choose) of the optional rules/missions.