Cadmus lay in his sanctum, staring down at his scrying pool. It was a large, silver vessel shaped like a wide crescent, filled with water from the eponymous lake. He dipped a claw into it, stirring gently. The face of the water swirled, and he saw his daughter running the registrar again. He also saw Zmerr going about his duties. Always the dutiful one. The silver dragon stood up and stretched. He thought to himself. While he could scry on many people and things, the assailant who had attacked his school was still unknown to him. Whoever he was, he was able to shield himself from scrying and other forms of divination. Well, perhaps not all forms of divination. 

When magic was pitted against magic, an arms race of sorts commenced. The ability of a mage to cast a spell was pitted against another mage's ability to block or dispel an enchantment. No spell, hex, enchantment, or curse was unbreakable, any more than a fortress was impossible to capture. The victor in this struggle would be the one who had a better grasp of magic, more magical power, and the faster reaction time. Until Cadmus had a clue on who his enemy was and how to counter him, the enemy had the initiative.