Timeline
Anthraxus is the ruler of Khin-Oin in the Forgotten Realms module Swords of the Iron Legion, which takes place in approximately 1357 DR (the equivalent of 577 CY in the World of Greyhawk Timeline). Anthraxus is still known as the Oinodaemon in the novel Artifact of Evil by Gary Gygax, in which he appears before the Hierarchs of the Horned Society just before their massacre by the forces of Iuz in 583 CY. In Planes of Conflict, whose in-game date corresponds to 587 CY, Anthraxus is said to have been recently deposed. In The Scarlet Brotherhood, which is set in 591 CY, Mydianchlarus is said to be the current Oinoloth, and to be an ally of the deity Pyremius. The 3rd edition Manual of the Planes (also corresponding with 591 CY due to its publication date) also describes Mydianchlarus as the current Oinoloth.
In Demonomicon, Anthraxus (called Phraxas in that book) is said to have taken his throne back from Mydianchlarus "only a century ago," which means that book must be set at least a hundred years after The Scarlet Brotherhood. Assuming the "present day" in Demonomicon is equivalent to the present day in the 4th edition Forgotten Realms setting (1479 DR, "The Year of the Ageless One"), then a century before that was 1379 DR, or 599 CY. This is still in the "future" relative to the last published Greyhawk products.
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