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After their brief clash with the drow, Alegni and his forces made their way to the primordial chamber and prepared to confront Drizzt, Entreri, and Dahlia. Meanwhile, the three companions traveled through Gauntlgrym and encountered Brach'thal and his lava elemental. The group managed to kill Brach'thal and destroy the elemental, and they then moved to engage Alegni and the Shadovar. While the trio battled the tiefling warlord and the Netherese soldiers, Ambergris betrayed her comrades by throwing Glorfathel into the primordial pit, stunning Afafrenfere with magic, and assaulting Effron.