The essence of greed is a consumable essence.

This small metal bottle contains the magical essence of greed, distilled from the bones of legendary thief Mithaldo, whose hunger for treasure was so great that he let himself be swallowed by a dragon in order to get at the jewels the beast had eaten through the centuries. When the dragon was slain some decades later, Mithaldo's bony fingers were found in the dragon's stomach, still clinging to a large diamond. (When absorbing a soul, the player receives much more health, but permanently loses one or more points of defence.)