Was it actually because of the Magic Spirit Potion?
Tris froze for a moment, then inwardly cursed himself for being careless.
Besides its main ingredients-basilisk venom, unicorn horn powder, and black dragon blood as a blending agent-the Magic Spirit Potion required more than twenty supplementary ingredients. Those, however, were nowhere near as rare as the main ingredients.
Tris had taken his basilisk venom from the thousand-year-old basilisk in the Chamber of Secrets, giving him more than enough; he had asked Hagrid for unicorn horn powder, and Hagrid, who often roamed the Forbidden Forest, had plenty of the stuff; the black dragon blood had come through his second-oldest brother, Charlie, costing over eighty percent less than it would elsewhere.
Since he did not need to buy any of the three main ingredients, he had figured the remaining ingredients did not warrant much concern. To be safe, though, he had still ordered them by owl post from separate apothecaries in Diagon Alley and Hogsmeade.
He had thought he had been thoroughly cautious, yet someone had still noticed something unusual. Worse, they had managed to trace the owls back to him.
He was frustrated, but he let none of it show.
Tris looked utterly bewildered. "What Magic Spirit Potion? What's that supposed to be? I don't know anything about it. Our Head of House never taught me about anything like that."
"Yes, I believe that." The wizard opposite him nodded. "Professor Snape certainly knows the recipe for this potion, but even he might not be able to brew it successfully.
"And at Hogwarts, the only person with a chance of brewing it is probably that great man. But he clearly has no need for such a thing. Still, young Mr. Weasley, given your age and the strength of your magic, we find it