Outremus said whatever the Balaur were planning, we should stop it by eliminating the Protectors who perform the ceremony. You killed Isbariya the Resolute at the Beshmundir Temple. While he was dying, he uttered some dire words of warning, which were followed by an ominous shriek from somewhere. When you reported to Outremus, he said that killing Isbariya might have been a mistake.