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Vindictus Viridian was a potioneer and author. He taught Potions at Hogwarts School of Witchcraft and Wizardry and became headmaster in the early 18th century. He died in 1703. Along with potions, Viridian was exceptionally skilled with curses, hexes and jinxes. He wrote a book called Curses and Counter-Curses that includes prank jinxes that cause hair loss, jelly-legs, tongue-tying and much, much more. This may have alluded to Viridian being a prankster during his student years, however, his portrait refuses to confirm this or not.

Two portraits of him can be found in Hogwarts. One portrait hangs in the Headmaster’s office along with portraits of other headmasters and headmistresses. Another portrait can be found at the Grand Staircase. Vindictus was quite an angry man during his lifetime. He had a very short temper and had little to no tolerance for stupidity, and his portrait reflects that. If you ask the portrait any relevant or productive questions related to potions, curses, or counter-curses, he will be happy to help you, otherwise he will hush you and ask you to leave in a very impolite manner.