Expending Fel Energy

Soon Kanrethad's banishment will fade, and he will return to our world. We must keep him, and his power, out of the Legion's hands at any cost. If my old friend is still in there somewhere, perhaps we can bring him back. The crystals you recovered feed on fel energy. We can use the ravenous crystals to siphon away the magic that consumes Kanrethad. But first, their power must be depleted. To do so, you will need to harness the power of the crystals and use their energy to kill demons.