King Ascertes Hallow was the human husband and consort of Queen Efaritay, the Icyene queen of Hallowland and father of their children Safalaan and Larina Hallow. Very little is known about Ascertes, but he was presumably born in the Third Age and married the queen some time before the Zamorakian invasion led by Lord Drakan. Ascertes was captured by Ranis Drakan and Verzik Vitur, who brought him to Lord Drakan. In Sins of the Father, it is revealed that Ascertes was turned into a vampyre during the Hallowvale invasion, in an attempt to end the ongoing war and force the queen to surrender to the Zamorakian invaders. After his vampyrification, he became known as Vanstrom Klause, and became one of Drakan's henchmen.