Wormcrawl's Southern Lake

The river empties into this large, still lake. Unlike its northern counterpart, this nameless lake is incredibly deep, with depths reaching as far as two miles into the Underdark below. The lake eventually connects to a hidden Underdark sea via numerous underwater channels. Its surface is placid and still, yet for all its peace and serenity, these waters are dangerous, as they have had all the time in the world to absorb the ambient taint and wretchedness that suffuses the stones of the Wormcrawl. The water is bitter and foul as a result, and creatures that drink of it are exposed to blinding sickness. No animals dwell within the near-freezing depths of this lake, although its deepest recesses hide something enormous and sinister-now and then, a glimpse of this unknown lake monster manifests in the form of mysterious ripples along the otherwise mirror-calm surface.