After Discord betrayed the ponies last time, Pinkie realizes she has made a grave mistake. She never threw a welcoming party for Discord! She hatches a plan to throw the biggest bash to make up for it, but she needs help to make it just perfect, throwing the surprise part of the party out the window.
Edit: Oh my gosh, how could I forget?
My pre-readers and editors, Phenrys and Sparky Brony, helped out with this. They deserve a spot on my page by now, as they've influenced pretty much all of my stories. Sparky in particular pointed out some major flaws with this. (sorry for forgetting you guys earlier)