Pazuzu was the winged demon prince of the Infernal Legions during the Chaos Wars at Nishnatoba. Khalas, the Wanderer, of the Triumvirate, discovered his existence, and appeared during the great battle of the Gods to route the Elder Gods. When the Triumvirate's traitorous plans failed, the Tribunal banished Pazuzu to the Chaos Plane, where he remained for some time, until an uprising within the plane saw him weakened and cast out.
Shortly after his arrival in the Chaos Plane, Pazuzu, Slith, and their Inferno Legions expressed alarm as their environment received the brunt of the chaos dispersed by Ayar and began to warp and mutate, creating chaos thralls - among them, Jy'Barrak Golgotha. Eventually, Pazuzu's arrogance and oversight let Golgotha stage a successful coup d'état, swaying even Danaeus, Pazuzu's chief advisor, to his cause. By Golgotha's command, Pazuzu, Slith, and Slith's chief advisor Zsarachnor were exiled to the Prime Material Plane.
While on the Chaos Plane, Pazuzu was summoned by the arcane rituals of the Tsol'teth lords Agith'maal, Terrin'ukia, and Gattan'lier. The demon prince appeared only briefly, much to the Tsol'teth lords' chagrin, and uttered only the word, "Seleucar", before vanishing once more into the ether.
In the year 758 AF, The Vigil secretly attempted to return Pazuzu to the his rightful rule and devised a way to use the Elemental War as their cover. They decided to sacrifice themselves in a ritual that seemed as though they were upon the four conduits of the Elemental Realm. It was successful, as the released energy was used to break Pazuzu out of his crystal prison in Kasmarkin. When released, Sh'Fah emerged from the Crystal Realm and sought battle with Pazuzu. The battle was intense but in the end Pazuzu defeated Sh'Fah. A number of adventurers decided to try and seal Pazuzu away by banging the drums to summon those from the Crystal Plane to come and seize Pazuzu. The adventurers were successful, but the Demon Prince fled to the Flame of Yggdrasil and sliced it, escaping into the World Tree and the many planes beyond while simultaneously opening the way for the rest of Achaea to traverse said paths as well. Sartan vowed to hunt down Pazuzu as he disappeared.