Soulsteel

Also called "darksteel" or "dark iron," soulsteel is an incredibly hard metal formed from the crystallized anima of the dead and dying. Found in the darkest reaches of Shadow, it is usually rather brittle, but when supplied with a source of fear, it can become harder than steel. Thus, a number of horrors have become talented shapers of the dark metal, using it in both combat and in more mundane tasks.