Ruby Knight, The (The Elenium)

Ehlana, Queen of Elenia, had been poisoned. A deep enchantment sustained her life, but only while the Knights aiding it still lived—and, already, they were dying, one each month. Then Sparhawk, the knight and Queen's Champion, learned that the cure for the poison was Bhelliom, the great jewel lost when Sarak of Thalesia died in battle 500 years before. Sparhawk and his companions set forth to find King Sarak's grave by raising ghosts of those who had perished in that ancient battle. The Seeker, an insectile monster spawned of the evil god Azash, hounded their every step. Still, Sparhawk pressed on, driven by desperate need. They had to find Bhelliom before his Queen perished. They must not fail!