The magic surrounding the alicorn fizzled and crackled, before fading from the air completely. Luna wasted no time in stepping forward and beginning to speak.
''Twilight Sparkle, we have-''
Almost instantly The Nightmare lifted herself into the air and darted between Luna and Twilight, baring her fangs aggressively.
''Princess Luna.'' She snarled furiously, cutting the other pony off. ''You are in another's mind, unauthorized. Explain yourself!''
Luna saw through the stalling attempt - she had gone through this process many times before, and knew the best way to get past it was to wave a hoof dismissively and carry on trying to save the victim. ''Be silent, monster. We have come to-''
A flash of magic, and Luna found her mouth wedged open with an apple.
Oh, of course Twilight had some memories of the exact same thing happening to her friend Pinkie that the Nightmare had picked up on. Luna growled behind the apple and spat it out. Life wasn't fair.
''You are not above me, Luna. Explain yourself now, or I will force you away from this place.''
Luna snorted at her opponent, knowing the Nightmare would never attack her while so weak - but even so she flared her wings in an attempt to make herself look bigger.
''Our sister is the princess of Equestria - both of us agreed we would traverse to Twilight Sparkle's dreams to save her from you.''
Twilight coughed, kicking at the ground awkwardly. ''I'm not sure I need saving.... The Nightmare can't do anything to me without my say-so, and she has a lot of knowledge. Do I need saving?''
Both mares turned to Twilight, never taking their eyes off each other.
''Yes!''
''No!''
Twilight sighed. ''Well, uh, Princess, I could stop this at any time - didn't you think of that? It is my dream, after all.''
Luna narrowed her eyes. ''We did, Twilight Sparkle. But the truth is you do need saving!''
Twilight bit her lip, and looked up. ''That may well be true, Luna. But I'm confused as to who I need saving from.''
Luna blinked, and Twilight could tell it took her a few moments to process what she had just implied - and she knew Luna would probably fly at one of them if she didn't break the tension.
She stepped between the two alicorns, waving a hoof to catch their attention. ''So could I please ask you a few questions?''
The Nightmare's eyes flashed. ''Ah, yes. Maybe we should find out why Luna tried to kill you before I enact my revenge.'' She said, her voice almost humorous.
Luna's anger snapped, and sprang into the air. Swiftly darting forward she connected her hoof to the Nightmare's jaw. ''We have not attempted to kill anypony - especially not Twilight Sparkle!'' She yelled, furious. ''We knew you would sow your lies quickly, but this is a new low!''
The Nightmare brushed off the blow, and simply went to stand beside Twilight. She looked down at Twilight, eyes questioning as she sent a message through their mental connection.
''Can I tie her down? If we don't she'll try and escape.''
Twilight hesitated a moment, but eventually nodded. ''If it means figuring all this out, I guess you can go ahead.''
The Nightmare closed her eyes, focusing her magic into her horn, and Luna quickly became encased in rope, an anti-magic bracelet ring and a wing brace ensuring she couldn't escape.
Luna yelped in surprised, writhing madly in a vain attempt to free herself. ''Twilight Sparkle! You are mistaken - we have not done anything wrong!''
Twilight sat down, ears flicking downwards. ''I'm sorry Princess - but I've no reason to believe you.'' Her horn flashed again, and Luna's vision suddenly flickered and faded.
''You have stolen our vision!'' Luna screamed, her frantic writhing increasing. ''Black magic! We expected more of you, Twilight Sparkle! Our sister spoke of you like you were a soldier of Light!''
The Nightmare winced at the metaphor, but Twilight stifled a giggle. Despite the seriousness of the situation, it was still kind of funny. ''I've blindfolded you, Luna. You can still see - but the material's stopping you from seeing anything but black.''
The Nightmare stepped forward. ''Now for the questions.'' She walked around to Luna, horn glowing steadily. ''I will use a truth spell on her, ensuring she won't lie as she has done so far. ''
Twilight nodded in approval, eager to get to the answers ahead.. ''Right! Let's get this all sorted.''
---------------------
Luna couldn't see anything, but she could tell the Nightmare had gone to stand beside her by her voice slowly growing in volume. She wasn't sure about having her enemy cast a spell on her - but she decided Twilight wouldn't let anything bad happen to her.
''Question one!'' Twilight sounded calm - but Luna knew better. She was hiding how eager she was to get to the truth, and also her initial fear at the fact she had tied up a Lunar Princess.
Luna nodded, opening her mouth to speak her approval - but nothing happened.
She tried again...and again, and again, and again - but she couldn't.
That's right, my little Lulu. I'm not a stupid monster, as you liked to call me back then. If Twilight thinks all I cast was a truth spell, she's sorely mistaken. Now, say something mean...Not too out of character, that'd make her suspicious - wait, she doesn't even know you! Oh, this is just perfect. Now then...Let's see, what about...
''Get on with it already, you stupid mare! Or are you too dumb to remember what you were going to say?!'' Luna snarled, baring her teeth angrily.
Twilight blinked and stepped back from Luna, the hurt evident in her eyes. ''Oh, yes, sorry Princess...''
What...What witchcraft is this?! Luna yowled inwardly. I am your better, release me at once!
Be quiet Lulu - you'll do better staying silent than you will do kicking and screaming - and what's this about being my better?
The Nightmare chuckled aloud - a cruel laugh that filled Luna with dread.
You and I both know Twilight Sparkle is stronger than you, Luna. Take an empowering spell and place it inside that kind of magical ability...Well, I think this explains why I'm the one controlling you.
Luna snarled angrily, and Twilight jumped.
''S-Sorry!'' She whimpered again, sitting down far away from the tied up Lunar Princess.
Guilt bit at Luna, and she wanted to explain - but opening her mouth would probably just end in the Nightmare forcing her to her insulting Twilight.
The Nightmare kicked her. ''Now, Luna. Be nice to Twilight.'' She said aloud.
iNow get ready. She spoke again, this time to Luna alone. We have a lot of things to say to Twilight...