If fighting dark wizards and trolls weren't enough, you can challenge your knowledge of the Wizarding World with Sophronia's quiz in the Library while searching for a Transfiguration book for your class. Seeing as you are coming from Transfigurations Class, you should know who published the Law of Elemental Transfiguration, no? Don't worry, we've got your answer.
Hogwarts Legacy - Who published the Law of Elemental Transfiguration?
Sophronia will give you three possible answers for this question. The correct answer is Gamp.
Gamp's Law of Elemental Transfiguration is fictional, but can be compared to scientific axioms like Newton's Laws of Physics. Gamp's Law digs into the fundamentals of Transfiguration Magic, describing what can be conjured and what can not. Generally speaking, one must change one substance to another. You cannot use Transfiguration Magic to create something from nothing. This explains is why food items are summoned from the Hogwarts Kitchens, rather than conjured in the Great Hall. The conjurations we use in the Room of Requirement likely come from Moonstones.
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One interesting exception to Gamp's Law is water. Water is a substance that can be conjured directly by magic, in particular by Aguamenti.
Also, in case you were wondering, potion ingredients can be conjured, but they generally don't work as well as the real thing. So your Potions grades might dip a bit if you try to cheat.
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