I dream idea for a possible story

I had a weird dream last night, but I remember only parts of it. It involved Twilight going through a cavern Metroid style and at once point in a cutscene she absorbs weird dark energy that evolves her, making her slightly taller and her horn longer (and maybe the start of some wings). Then later she encounters Applejack, and for some reason (I think after saving her from a boss) Twilight evolves again. This time, however, her body absorbs so much of this dark energy that she turns into a Changling Qween, but with her own unique hair and appearence from the neck up and a sad look on her face. During her evolutions her whole body turns into a black shilloete, the background turns dark like in a Mortal Kombat Fatality, and there's no music except for a wublike humming noise that supposed to be the energy being absorbed. The characters and environment somewhat similar to the graphics of Super Matroid. I remember there was suppose to be a 3rd transformation into a full Alicorn like Celestia but the dream ended before I got to that point. Maybe she got purified or something.