Sigmund Brock



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Professor Rotwood's mentor, a researcher of the magical world, and inventor of Brockium - a chemical that will make any disguised dragon revert to its true form - he was a professor at Fumshteiken University when Rotwood was a student there. Brock is brought in to replace Rotwood as Principal of Fillmore Middle School when Jake gets Rotwood fired.

However, because he had Brockium and was determined to catch the dragon at Jake's school, Jake had to get him fired as well. He even resorted to forming an alliance with Rotwood to do so. In the end, Brock was fired and Rotwood was restored to position as Principal.