A horrible threat hangs over the Kingdom: but for once it does not issue from Xax and Kreel. The evil sorcerer, the Magus Zadrim, has been working in concert with the scientist Voss to develop a horrifying new strain of a deadly virus known as the Yttrium Element. Voss has succeeded in rarefying the Element to the point where once added to water it multiplies its strength a hundredfold: any living thing coming into contact with the contaminated water will die horribly. Triumphant, Zadrim comes to Xax and Kreel and issues his ultimatum: either they will surrender half the kingdom to him, or they will find themselves ruling a land made up entirely of dead settlements ... At Kalem's counsel Will sends Aruna to the house of Athelstan, Voss' Master, to pose as his assistant. She rapidly discovers Voss' plan and she and the band pursue him toward Zadrim's Eyrie, where Voss is scheduled to sell the flask containing his deadly invention. But on the way Zadrim snatches the flask; and Will finds