A potion that gave the drinker a sudden and inexplicable sense of euphoria and happiness. Harry Potter brewed the potion in response to Professor Slughorn's brief to the sixth-years to make something 'amusing'. Once Harry realised the Half-Blood Prince had heavily altered the recipe, it seemed the perfect way to satisfy Slughorn's request, impress him and put him in a good mood - all in the hopes that this would aid Harry's mission to retrieve a memory. With the help of his altered textbook, Harry added peppermint which Slughorn noted would counterbalance side effects of excessive singing and nose-tweaking.