Botmundo

This strange bottle dates back to the late 19th century. Obscure writing states that it was made in Baltimore, U.S.A. For adults only!

Drinking this bottle will reverse your ageing process. Each birthday you celebrate will make you one year younger until you’re 16 years old again. The effect of the brew will remain even after you turn 16 at which point it will prevent further ageing. The only way to remove the effect of the Mr. Button's Brew is to have it removed with a special antidote.

Drinking the bottle will also grant you a personalized t-shirt with a text saying something like '60 going on 16', but with your current age replacing the number 60.