In an alternate ending to ‘Rainbow Rocks’, the Dazzlings still suffer failure, but their powers remain.
However fortunate, the repercussions are far worse than they can imagine, as Princess Twilight wishes to ensure the safety of both worlds by taking one of the Dazzlings back to Equestria to try and reform her. A “ward” if you will, which to the Dazzlings is just a fancy word for “hostage,” for if the other two act up, the ward will be sent to Tartarus, or worse.
Follow the Dazzlings as each copes with this situation.