Seasons ago, the princesses used magic beyond their understanding and accidentally created a new, unique being in the process. Now, with the spell’s original creators back from Limbo, they are determined to make things right.

Twilight Sparkle gradually realizes that something else is living her life.

As a result of a magical mishap in the name of protecting Equestria, the princesses fuse into a single being. But in order to bring them back, she will have to stop existing. What does it mean to die?