Deep Imaskar, also known as The City of the Great Seal, was created during the fall of the Imaskar Empire in −2481 by the wizard lord Ilphemon as a safe haven for his followers and family. The fled carrying an artifact of immense power, the Third Imaskarcana. The city was located in the lower Underdark, somewhere below the Endless Waste. As of the Year of Lightning Storms, 1374 DR, it housed the largest group of surviving descendants of the Imaskar empire, but this changed with the founding and growth of High Imaskar sometime after the Spellplague.