A Tangled Web
The quest "A Tangled Web" is provided by the Gray Goblin Jaacar. In exchange for a bag of treasure, you must kill 12 blood creatures - the known creatures are a Bloodworm or a Blood Elemental - any combination of the two will do.
He gives you a barrel (not physical) that you must fill with blood. What does a goblin need a barrel full of blood for? Hmmm.
It does not appear a character may do this quest twice.
Bag of Treasure reward is probably random, but one bag contained 5 amber, 5 tourmaline, a composite bow with low stamina leach, a cap & hat - nothing of real value.