Dwarfbane

Dwarfbane was a poison that was especially effective against dwarves.

Description
Dwarfbane was gummy in its consistency.

Uses
The duergar of the Underdark often coated darts and other weapons with this poison for the use in traps.

History
Though the duergar were completely immune to the poison, dwarfbane was lethal to all other dwarves.