"Oooh, look, powdered horn of a bicorn — don’t know where we’re going to get that — shredded skin of a boomslang — that’ll be tricky, too and of course a bit of whoever we want to change into.”
-- Hermione Granger after reading Most Potente Potions (CS10)
Shredded boomslang skin is used in Polyjuice Potion.
- Hermione finds boomslang skin in the list of ingredients for Polyjuice Potion in the book Most Potente Potions, found in the Hogwarts Library Restricted Section (CS10).
- Hermione stole boomslang skin from Professor Snape's Office after Harry and Ron created a diversion by blowing up Goyle's cauldron (CS11).
- In fourth year, Professor Snape accused Harry of breaking into his office again and stealing Polyjuice Potion ingredients again, including boomslang skin, and threatened to put Veritaserum in his pumpkin juice to prove it. However, that time it was actually Barty Crouch, Jr., who was disguising himself as Mad-Eye Moody using Polyjuice Potion (GF27).
The author wrote that she chose boomslang skin as an ingredient for Polyjuice because the person who takes the potion "sheds" their outer skin while staying the same underneath (Pm).
Ingredient in Polyjuice Potion.