Hellfire Forge

The Hellfire Forge is a device added by Blood Magic for Minecraft 1.8.9 and above. It is needed to craft recipes requiring Will, which requires Demonic Will or a Tartaric Gem in the right slot that has enough default will to meet the required minimum will. The drain amount will be subtracted from the stored will. The Demonic Will/Tartaric Gem will not be lost. Both minimum and drain will amounts can be seen in NEI/JEI when hovering over the arrow.

A second use for the Hellfire Forge is filling Tartaric Gems. A Tartaric Gem in the right slot will drain from the aura in it's chunk. For example, melting Corrosive Will Crystal inside a Demon Crucible will fill the chunk with corrosive will, which will then fill the Corrosive Tartaric Gem inside the forge.