Obsidian Citadel

The Obsidian Citadel is a symmetrical complex of towers and walled defenses in the Yatil Mountains. Its the home of Mordenkainen. Fierce winds and swirling clouds, and also illusions, disorientating magical effects causes the searcher for the citadel to become confused and lost. Magical defenses also prevent access by such spells as plane shift or teleport to "unauthorized" persons, and the Ethereal plane to confuse those who would seek to enter by this route. Those whom Mordenkainen wishes to approach and enter are given magical amulets by the archmage which effectively act as find the path spells (one use per amulet only) so far as locating the citadel goes.

References

Zavoda Index Entry

The Encyclopedia Greyhawkania Index page has a list of sources, abbreviations, and a link to the full index.