The crucible is a more advanced variant of a furnace. It works not by refining raw ore, but mixing refined metals into more advanced material. Armor such as Redsteel, Endersteel, and Moonsilver is created by using a crucible.
Recently, Villagetown acquired crucibles from the Lost Legion. Leaf and Extreme, two blacksmiths in the village were locked in a fierce business rivalry. With a crucible, Leaf was able to construct walls of a strong material called "spellforged steel," and build a shop right next to Extreme's. Unfortunately, the shop was destroyed in a raid. Although Leaf says that his walls would not be burned down by even void fire, it is completely melted down by three pigmen using their ult - Meteor Storm. This shoots out a torrent of void fire.