The Dragonfire Forge is hidden in the mountains to the north of the Orrery. The finest Artificers and smiths of the Basilisk Order worked in this ancient furnace doing their best to re-create the arms of the Progenitors. The military might of the Basilisk was cast here.
The cavern mouth is fitted with a portcullis to keep intruders from wandering in, it served only to prevent the escape of those inside. The undead have no use for ancient weaponry, but to cut the supply of their enemies was cause enough for the attack. The cavern was collapsed, with all inside presumed dead.