Demon's Tail

Demon's Tails are a common drop and herblore and crafting ingredient from demons.
Players can use Demon's Tail to make a Threat Potion I, II, III, or IV.
They can also use it to make [Hardgrip Rope].
===Source===
They drop at a rate of 75% from Demons. (The big variation, as they do not drop from Imp-Class Demons.)