The Illearth War is a fantasy novel by American writer Stephen R. Donaldson, the second book of the first trilogy of The Chronicles of Thomas Covenant series.

Angered by the fact that he has been transported away from "reality", Covenant nevertheless believes he is once again experiencing a dream or delusion due to his head injury.

For forty years, the Lords have dedicated themselves to the study of Kevin's Lore, training new students at the school at the tree city of Revelwood.

The Warward, the army of Revelstone, is full of battle-ready volunteers and is led by Hile Troy, who came to the Land from Covenant's world.

With the aid of the powerful Illearth Stone, the Ravers, Foul's non-corporeal servants, have possessed the three brothers, now renamed Kinslaughterer, Fleshharrower, and Satansfist.

Hile Troy is a genius in military tactics who developed a mystical form of sight when hurtloam, a magical mud with miraculous curative properties, was used to try and "heal" his lack of eyes.

Covenant, Elena and their two Bloodguard protectors journey through the remote mountain region on the western frontier of the Land to the hiding place of the Ward.