Askume

Askume was a fungus that grew in the Underdark.

Description
Askume grew in patches on warm cavern walls. Each reddish-orange patch was in diameter.

Uses
Each patch of askume, when crushed, could yield 2–4 applications of a dust that could be blown into the face of an individual. The dust caused an allergic reaction making the recipient's tongue and windpipe swell, leading to suffocation and possibly death.

Those who purposely grew askume and sold it were vigorous in their protection of the patches for a dose of the poison could sell for up to 150 gold pieces each.