"You've found Thaumatagoria! I always thought it was a myth! A story told to excite potion-makers, to make them dream impossible dreams! The rumours about its properties are legendary, you wonderful, wonderful young potioneer!"
-- Zygmunt Budge (BoP)
Thaumatagoria is an extremely rare magical plant, thought by many to be mythical. It was used by Potioneer Zygmunt Budge to create the Potion of All Potential (BoS).
thauma = Greek for "miracle, wonder", from which we also get the word "thaumaturge", meaning "a worker of wonders or performer of miracles, a magician." (Dictionary.com)
The name of this plant was difficult to understand from the audio of the game, but it was confirmed from "Book of Potions" Game Files by Harry Potter Wiki.
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