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The Princesses’ final option in dealing with problematic characters.
 
Princess Luna has the unredeemed but mediocre antagonists shrunk down and locked up in a box while the repentant antagonists are equally tiny but are free to roam around her much larger residence. However, still feeling her own regret about the Nightmare Moon matter, Luna all but insisted that she must also be shrunk down so as to avoid any indication that alicorns are above justice. Princess Celestia promptly compromises and decides that Luna should effectively be akin to a warden for the others. Meanwhile the worst antagonists get eaten by Celestia.