My little Theory

Looking at To Where and Back again a question has been on the back of my mind how did the changelings get Twilight and the rest of the mane 6. I can tell how they got Celestia seeing they did it before and they could have use Celestia's life to get Luna, and with Cadence and Shining armor they also have past experence and Cadence is not that powerful, other then this.

She doesn't seem that powerful(and before you say king Sombra, that was the crystal heart and the crystal ponies, not Cadence). And Flurry heart is a baby. I kept thinking about what the answer might be, then it came to me. it was so simple and obvious I couldn't believe I hadn't though of it before. Chrysalis kidnap the mane 6 in there sleep. It explains why the other ponies didn't find out or hear a commotion because a alicorn who came do this

is fighting changelings. I think Discord magic is as powerful as Celestia's, Luna's, and Cadence's put together that would give you a picture of how powerful Twilight is. Lastly some of you might ask but Twilight couldn't beet Starlight. That answer is simple. Twilight knew how powerful she was and during the battle she held back. She did not want to bring Starlight or any witnesses any harm. as for the rest of the mane 6 they must have thought "the rest of are foes are right hear, lets grab them".