After having a stern talking to from the Cakes, Pinkie feels she needs to start taking her life more seriously. She begs Twilight to use a new spell to change her personality so she will be more 'serious bu-derious’ and not silly and random. Twilight uses the spell but instead it ends up giving her horn to Pinkie and while Pinkie is a very intelligent and studious unicorn, Twilight is a silly and random Earth pony who wants to constantly throw parties. Pinkie must put up with living like this for an entire day and keep anyone else from finding out that Twilight was also affected. It will all be fine, the personality-switch spell will be over in just 24 hours..........or will it?

Original release: May 21-29, 2011 on Deviant Art