The Web of Wizardry by Juanita Coulson

They appeared from nowhere…

… An implacable horde that ravaged the lands of Krantin, slaying and taking their own death wounds in eerie silence.

The outer islands have fallen, and soon the sorcery-driven soldiers will be striking at Krantin’s heart.

The only hope for survival lies in an alliance of Royal forces with the fiercely independent desert marauders, the Destre-Y — and with a perilous linkage of all of Krantin’s adepts of magic.

The young Troop-Leader Danaer, Destre-born but sworn to Royal service, is the key to the uneasy partnership of ages-old enemies.

But his love for the enchantress Lira is now imperiling the final confrontation between the malignant enemy sorcerer and the protection of the web of wizardry…