Overking is a title generally used to refer to the monarch of the Great Kingdom, though it is also (mostly internally) applied to the monarchs of some Great Kingdom successor states. The title is equivalent to that of emperor.
Malachite Throne is sometimes used as a synonym for the office of the Great Kingdom's monarch.
The following contemporary and historical nations title their monarchs overking:
- Gygax, Gary. The World of Greyhawk. Lake Geneva, WI: TSR, 1980.
- -----. World of Greyhawk Fantasy Game Setting. Lake Geneva, WI: TSR, 1983.
- Holian, Gary, Erik Mona, Sean K. Reynolds, and Frederick Weining. Living Greyhawk Gazetteer. Renton, WA: Wizards of the Coast, 2000.