"No, it's not - " Draco started, and hesitated. "Well, not really. It might have similar effects if I get it right. Maybe better." He crossed his arms and leaned against the wall, trying to look as if he didn't care what Weasley did. "Who's going to brew Wolfsbane? That's a very difficult potion to get right, you realise. Getting it wrong could have all kinds of consequences - killing them, for one."