Pinkamena Diane Pie

Vigilance.
Whenever you cast a spell with a smile in its art, put
a finality counter on target creature.
Everypony's not Invited — Your party consists of none creature you control, and your party is always empty except them.
When Pinkamena Diane Pie would leave the battlefield while there are four or more creature with finality counter on it.Transform into one of them instead.