Sigmund Brock

A villain in the animated series, American Dragon: Jake Long.

Info
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. Needless to say, he's more of a threat than Rotwood.