The time of the Great Old Ones fast approaches. Soon, Equestria will play host to entities from beyond the stars.

But first, there is the matter of preparations...

When Pinkie receives a mysterious letter from "Mr. N", claiming to need her skills to throw a massive party, she is more than happy to oblige. But as the preparations go on, Pinkie begins to realize that there may be more to the party and to her mysterious Patron. As night falls and the party begins, Pinkie soon finds that her actions may bring about the final, dark age of Equestria...

A My Little Pony/Cthulhu Mythos crossover.