Kazrith

A Kathrith was an aquatic demon that could be found prowling murky lakes, underground waterways, and flooded tunnels.

Abilities
A kazrith used tremorsense to detect enemies; after locating a target, it surfaced and attacked, poisoning its victim. The demon waited until the prey was weak from the poison, then resurfaced and finished it off. This demon was also a skilled burrower, using the acid in its pores to excrete a trail of acid in the tunnels it made.

Ecology
Most kazriths dwelled in the Elemental Chaos, but some occasionally found natural gates leading into Toril. Kazriths created vast networks of flooded tunnels between lakes and other bodies of water. They could then travel easily from habitat to habitat. These tunnels were usually not far below ground, so the monsters could sense potential prey walking above them.

Society
These demons were often found in the company of other sinister aquatic monsters.