A'aroc's Viscid Oil of Hell Hornet Venom  is harvested from the sting of the Hell Hornets, which originate from the Elemental plane of Fire.  The usual method is to coerce several of the hornets to sting an asbestos sponge.  The sponge is then rung out into a mortar and mixed with a preservative and a toxic thickening agent.

This salve has 5 applications that can be put on any piercing or cutting weapon, which only lasts for one hour or one successful attack.  It appears as a iridescent green slime coating the weapon's edge.  If a target takes damage from a weapon with this poison on it he is poisoned (no save/burning muscle spasms) until the end of his next turn.  At the end of his turn he must also succeed on a DC 8 Constitution saving throw or gain one point of exhaustion and take 2d6 poison damage (save for half).  Casting Protection from Poison (or other such  healing magics) within one hour of the attack will cure 1 point of  exhaustion.

Notes: Exhaustion, Poisoned