So they were making an antidote. Made sense given the ingredients, and the fact that it was the Healer teaching them. Sam made some notes on her parchment, but really had some questions for Addy later. Like...what differentiated this antidote from numbers 1 to 4? When should she use this one over the others? Or the others over this one? It seemed important information, even if she hoped never to have to use it.

But the Healer had questions for them right now. "Basilisk venom is so potent it can destroy horcruxes." That definitely seemed like a benefit of a poison. And as for uncommon poisons, it seemed the class had already got it covered.

Uncommon poisons were ones that weren't readily attainable, but weren't super rare either. Ones that weren't naturally available, or easy to brew at home, but were still reasonably affordable if someone knew where to go obtain them. Her Pa had dabbled in selling such things on the black market, once upon a time, before he'd been sent to Azkaban. She could probably still name some of them, if she thought back, even though she'd only been young at the time. Of course, she didn't actually feel the need to mention that knowledge aloud, and thus just waited for the next part of the lesson.