Have you grown too strong, too wise, too cunning, too toothsome for your own good? Disgrace yourself. [If for some reason you wish to reduce your primary abilities, this will help. You may sometimes get further rewards, but the key effect here is just to damage your abilities.]
The gentleman who serves you pauses, one hand on the bottle. "I beg your pardon. I can't recall exactly what it was you wished to purchase. Or why the sun has gone out."