Soul coins are the magical currency of the Nine Hells. They are composed of a hellish iron called inferno steel. They are large coins measuring 5 in (13 cm) in width and 1 in (2.5 cm) in thickness. They usually weighed about 0.33 lb (150 g). On the front-facing side, an abstract design is etched onto its surface, and the back features an infernal script. Soul coins are made by compressing a human soul into a coin through hellish magic. The soul is tormented while in the coin; the more despair, the more its worth. Non-evil creatures are only able to carry a few coins at a time, while evil creatures can carry as many as they wish.
The coin possesses innate powers that are quite powerful. The coin could be used to drain the life of a targeted creature or communicate with the soul within telepathically. It can answer questions, but often it is vague, and they seem tortured to do so. It is possible to release the soul within a coin, but it is tough.
Yandreak Wildmight has figured out another purpose. Somehow, he can use the soul coin as a binder to create Arcaneborn.