|Xuất hiện lần đầu||Harry Potter and the Goblet of Fire|
While the effects of this potion are never described, it can be assumed from the name that it is intended to increase perceptiveness or "wit". We do learn that the principal ingredients are powdered scarabs, ginger root, and armadillo bile, but unlike some other potions, we do not hear this one's finished state described.
The overall purpose of this potion in the narrative seems to be marking a change in concentration in the Potions class. In the earlier part of the year, up until Christmas, Potions had been centered on antidotes. Harry had found this topic particularly unnerving, as he expected Snape to poison him as part of the term-end test, to see how well Harry had made his antidotes. While the Second Task occurs nearly two months later, on 24 February, and this class occurs after that, we do not see any Potions classes during the intervening months; this is the first Potions class we have attended with Harry since Christmas.