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Since the Beginning of Time the forces of Order and Chaos have been engaged in an eternal struggle to decide the fate of all Creation. That struggle has now come to the Mortal Realm... And neither Man, Demon, nor Angel will be left unscathed... In the Diablo II Expansion Set, you will return to follow the path of Baal, the last of the Prime Evils, into the Barbarian Highlands of the north. Traveling with hordes of demonic minions, Baal intends to corrupt the powerful Worldstone that protects the whole of the mortal plane from the forces of Hell. You will face a new series of quests and challenges to prevent the vile minions of the underworld from destroying the world of Sanctuary.