khaelin04 
Here's an idea, the tree is closing up on Opaline sealing her away, but in her last moments she finds a picture Misty had drawn of her, her thoughts wondering. I'd imagine while she's sealed away, she'd reflect on everything that's happened, as being a kids show nobody actually dies. (Maybe except a few... such as Sombra...) (Now I'm wondering about Terrible Trio as stone in Gen 5)