Blood weed

Blood weeds were carnivorous vines that could grow underground or in sewers.

Description
Blood weeds fed on the blood of creatures. Each weed was a long vine covered in cruel thorns designed to ensnare and drain blood from passing victims. They were highly resistant to being cut or bashed aside, but were susceptible to extreme temperatures such as fire or magical cold.

Ecology
Blood weeds grew underground, and would worm their way through cracks to form into dense clumps that could block tunnels. This made them suitable as traps, hazards, or obstacles in dungeons.

Blood weeds had been observed in tunnels beneath Waterdeep's Dock Ward.