The Last Days of Ilam
Dracolich of the Corpsetower
After Tan Lin gains the Regalia of Evil, Korgax recognizes that Lin has exceeded him in power and hands the position of First Mage over without a fight. Korgax is seen defending The Corpsetower during The Third Tower War.
Many believe that Korgax regained the tower after the third war, but no one knows for sure.