He tilts his head reflectively. "I could certainly re-create the variant, if that's what you mean. Whether the effect could be re-created, I couldn't say. At the time, it was mixing with a reconstruction of Mithridate, the venom of a snake-familiar burdened with the Horcrux curse for which in two years I'd failed to find any specific antivenin, the long-term residuals of Dementor exposure, and whatever classroom garbage the period since actually teaching potions had failed to flush from my system. I have no idea whether any interactions took place."
Severus nods. He'd intended to retire into his brewery, and look how well that had gone.