Perhaps you can end it with Celestia look over at the ponies in Ponyville and they're all causing damage to the town because they're doing the Bird Box challenge, all of it being imagination and the ponies are just doing the Bird Box and causing damage. Celestia and Luna just facehooves at them in disappointment, saying "Why do ponies take these trends too seriously?"
But again, if you have an ending idea, go ahead. I just wanted to tell you my silly idea.