Page "Greyhawk" Paragraph 75

However, in 2003, Gygax announced that he was working with Rob Kuntz to publish the original castle and city in six volumes, although the project would use the rules for Castles and Crusades rather than Dungeons & Dragons.

Since WotC still owned the rights to the name Greyhawk, Gygax changed the name of the castle to Castle Zagyg — the reverse homophone of his own name originally ascribed to the mad architect of his original thirteen level dungeon.

Gygax also changed the name of the nearby city to " Yggsburgh ", a play on his initials E. G. G.