If there was an opportunity for Harry to brew potions, he was going to take it. Yes, he did this for a living. Yes, potions was the default thing he thought about whenever there was nothing else to occupy him. But this was competitive and therefore, somehow, a separate category of potion making in his mind, and therefore novel.

Listen, it all made sense if you were insane.

Needless to say, Harry was well-versed in Essence of Insanity, so he set about brewing it with his usual confidence.

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