The Anvil of Ongruxiel is an anvil made of demiurgic iron. In the Demon Spawn War, demons under Orcus found this material scattered about Sotiisk'lum. At the time, this valley was nameless, its legendary history not yet recorded of when had been a forge area for Ares and Tarâk. When demon scouts came to this area, they noted the destroyed framing that was used to create something colossal in size. They salvaged some of this iron, hauling it back to the Abyss world Thanatos.
The head of Orcus's forge at Naratyr was a babau named Ongruxiel. This demon built an anvil of demiurgic iron and then submerged it into a vat of angel blood. The result, after powerful enchantments were laid upon it, was an anvil that produced weapons that were very dangerous to angels. Ongruxiel created thousands of arrow heads on this anvil and supplied them to Orcus's arrow demons. When these arrow demons of the Angel Blood Division were sent to Bal-Kriav, they tore through the armies of the gods and angels. After a year of steady fighting, they had control of nearly all of the what is today known as the Aerie of Dragons.
In 9007 GE, Atlas, Lukoon, and Phalgas were sent on a secret mission to Thanatos. They headed for the fortress of Naratyr. Luckily for them, Orcus and a large part of his forces were moving to battle an invasion by angels under Dispater. The garrison was still expected to number in the thousands, so Lukoon came up with a plan to use Orcus's pet against the garrison. After Lukoon found a way inside Naratyr, Phalgas moved to grab the attention of Cerberus, and then Atlas used his seemingly unlimited strength to break the chain holding back the demon hounds. When Cerberus realized he was free, he lost interest of the angels around him, and instead went after those that had taunted him for centuries. Cerberus tore through the demon garrison of Naratyr. While the demon hound drew away the demons, the angel trio made their way to the forge. In this area, they came upon Ongruxiel. He proved no match to three angels destined to become gods. None of the angels were willing to touch the accursed anvil, so Atlas wrapped it in a section of Cerberus's chain and carried it out of Naratyr.
Back on Bal-Kriav, the anvil was taken to the highest mountain of the Aerie of Dragons and then purified of its evil taint. This was done by dropping a thimble of Bal-Kriav's blood on it, and then forging a non-evil item on it. The Anvil of Ongruxiel became a redeemed magic item. The angels and their allies used it for the rest of the Demon Spawn War to forge great pieces of armor and weapons for the fight against the demons.
When the gods and angels left the world Bal-Kriav to the mortals, the anvil was left at what is today known as the Cloud Forge. This forge, atop the highest mountain of the Aerie of Dragons, has been used to create non-evil armors and weapons of epic quality. Those that have tried to make evil items here have either been destroyed or driven off by the Chain of Cerberus. This is the same chain that Atlas used to wrap up the anvil and bring it back to Bal-Kriav. This massive chain is now a powerful construct rivaling the might of a dozen blutium golems.