The Untheric pantheon were originally housed on the plane of Zigguraxus, brought over from another world by slaves imported into Faerûn by Imaskar. Like the Mulhorandi pantheon, the Untheric gods were initially barred from contact with their followers by a planar barrier erected by the Imaskari; however, also like the Mulhorandi gods, they bypassed this problem by sending physical manifestations of themselves to Toril via the Astral Plane. With their divine power backing them, their followers were able to overthrow the Imaskari and build a civilisation for themselves.
The pantheon made few friends among the other gods, but many enemies then, during the Orcgate Wars, the pantheon was devastated by the loss of seven of its members at the hands of the Orc deities while another, Tiamat, was banished to the Nine Hells.
Gilgeam became more and more despotic over time and grew to be hated by the people of Unther. When the last of Tiamat's cultists summoned an aspect of her, she began to forment plans to overthrow the God-king and she regained her status as a god with the resulting swell of worshipers who shared her goal.
Everything came to a head during the Time of Troubles. Tiamat brazenly attacked Gilgeam but was seemingly killed in the battle. Due to Tiamat's decade-long planning her essence was soon reformed into a new body and she again attacked Gilgeam. Surprised and weakened, Gilgeam was killed. Soon after, Assuran killed his enemy Ramman. With only two gods of the pantheon left, rather than share power, Tiamat and Assuran joined the Faerûnian pantheon instead, dissolving the Untheric pantheon and making Zigguraxus disappear.
The members of the Untheric pantheon were as follows:
- Assuran (demigod, joined the Faerûnian pantheon)
- Enlil, the patriarch of the Untheric gods.. He abdicated in favor of Gilgeam and left Toril in −734 DR.
- Gilgeam (intermediate deity then demigod, killed during Time of Troubles)
- Girru (killed during the Orcgate Wars)
- Inanna (killed during the Orcgate Wars)
- Ishtar. Shortly after the departure of Enlil, Ishtar gave the power of her manifestation to Isis and vanished from Toril as well.
- Ki (killed during Orcgate Wars)
- Marduk (killed during the Orcgate Wars)
- Nanna-Sin (killed during the Orcgate Wars)
- Nergal (Killed during the Orcgate Wars)
- Ramman (Killed during the Time of Troubles)
- Tiamat (Lesser deity, then archfiend, then demigod, now a lesser Faerûnian power.)
- Utu (killed during the Orcgate Wars)
- Eric L. Boyd (September 1997). Powers & Pantheons. Edited by Julia Martin. (TSR, Inc.), p. 96. ISBN 978-0786906574.
- Eric L. Boyd (September 1997). Powers & Pantheons. Edited by Julia Martin. (TSR, Inc.), p. 94. ISBN 978-0786906574.
- Scott Bennie (February 1990). Old Empires. Edited by Mike Breault. (TSR, Inc.), p. 5. ISBN 978-0880388214.
- Eric L. Boyd (September 1997). Powers & Pantheons. Edited by Julia Martin. (TSR, Inc.), p. 95. ISBN 978-0786906574.