Opaline catches a young Misty playing with butterflies outside early one morning.

So as I'm uploading this, I am just now learning about the new toy of Misty that was revealed on Equestria Daily, along with her official cutiemark (At least I assume so). I speculated that her cutiemark would indeed be a butterfly due to some references: Misty's fake cutiemark resembles a butterfly, and she even incorporated a butterfly wing in her Nightmare Night costume. It got me thinking about what significance the insect has in her life. I did a bit of research and I learned that butterflies symbolize so many things including transformation, comfort, hope, and even freedom. All of these relate to Misty and her situation perfectly as Opaline's timid subordinate.

As a filly, Misty would wake up early every morning to sneak outside and play with butterflies that often gathered on the hills and in the meadows near Opaline's castle. These were the only moments where the little one truly felt free and where she could be herself. She would chase them around, let them land on her nose or horn, and just generally watch them flutter by. She absolutely loved them. But one faithful morning, Opaline caught her and ceased her playing for good, locking her in her room in the castle until she learned to "Behave". As Misty grew up and as she began to travel to Maretime Bay on her tasks for the alicorn, she continued to show her love for butterflies by drawing a fake cutiemark that resembled one on her flank, even though she was no longer allowed to play with them.

That's my take on it. I really think they're going somewhere with it, now that the toy has been unveiled. I'm not sure what particular talent the cutiemark would represent, but as it resembles a butterfly, it could symbolize so many things that relate to Misty herself. When Opaline is defeated eventually, I think Misty will end up being the one to do her in, or at least be a key figure who is instrumental in her downfall.