King Sombra smiled politely and said, "I must admit that when Celestia said she would send help, I certainly didn't expect this."
"And what do you mean by that?" 'Black Knight' replied evenly, waiting to see how much his alternate self would reveal.
"I was lead to believe that those who are good in your world are evil in mine and vice versa," the king replied. "For her to send my counterpart seems like trying to put out a fire with oil."
Before the former tyrant could reply, he was surprised by another speaking up. "With all due respect, your highness," Rarity said, "his name is actually Black Knight, despite the uncanny resemblance."
"Yeah, Princess Celestia vouched for him herself!" Rainbow Dash added.
"He's a lot nicer than our King Sombra was," Fluttershy said. "Although I suppose that's not saying much..."
"We saw him explode!" Pinkie Pie shouted.
"Our Sombra, she means," Twilight clarified. "I know you've just met us, but I give you my word that we're all here to help, including him."
"My thanks for your faith, as always, Lady Twilight," 'Black Knight' replied. "The rest of you have my thanks, as well, even if the support was unexpected."
"Of course we'd back you up," Rainbow Dash said. "After all, what are friends for?"
"Friends?" He mumbled in stunned confusion.
"Wait, if you were expecting help, then why were we almost arrested as soon as we got here?" Asked Applejack, who had remained conspicuously silent when the others had come to the stallion's defence.
The king turned to the guard and raised a single eyebrow questioningly.
"My apologies, your highness," the guard said. "We mistook them for the Mean 6, that group of troublemakers that sometimes comes around from Ponyville."
"Then you need to listen better when I give orders! Now, get back to your post," The king snapped. Scowling at the retreating guard, he turned back to his guests. Giving an apologetic smile, he said, "My apologies, the recent threats to the kingdom have left my temper rather frayed." Gesturing towards the balcony, he went on, "Now come, we have much to discuss."
"Is it true that the Elements of Harmony don't exist in this world?" Twilight asked.
"Indeed, or if they do exist, nopony has found them yet," he replied. "And I'm glad Celestia sent the six of you... among others. I've really run out of options and I'm desperately in need of aid. I've heard so many stories of your use of the Elements in saving your home world. Celestia has done little else but talk of how proud she is of all of you." Turning to Twilight, he added, "Especially you, Twilight Sparkle." His smile fell away as he examined the young mare's glowing eyes. "Although, on her most recent visit, she seemed rather concerned about-"
A shrill scream from Fluttershy suddenly cut him him off. Following her gaze, the others looked up to see a terrifying sight.
"Well, well, Sombra!" Luna said as she descended towards the group, resplendent in black and red royal adornments. "Who are your new little friends?"
"Heh, where's that pretty lady friend of yours?" Celestia asked with a sneer, her own golden crown reminiscent of dragon horns. "I wasn't done playing with her when she left."
"What are you two doing here?" King Sombra demanded. "Haven't you caused enough trouble of late?"
"I'm just here for a friendly 'hello'!" Celestia said in an all-too-innocent tone. "Have you reconsidered my offer?"
"You and your offer can go buck yourselves!" King Sombra snarled back.
Twilight opened her mouth to intervene, but hesitated when she felt a hoof on her shoulder. "Not yet," 'Black Knight' whispered to her. "He's obviously used to dealing with this pair, so let us see how he handles it."
"Come now, Sombra, I'm really being quite reasonable," Celestia said with a smirk. "Just tell me how to get to the other world, and you won't have to worry about us causing you any more trouble in this one. I'll even let our counterparts come over here to help you clean up!"
"Although it won't be our fault if we have to get a little rough while convincing them," Luna said with a snicker.
"I would never agree to put another world at you mercy! Now, leave!" As King Sombra finished his declaration, a beam of magic shot forth from his horn, striking the ground between him and the two alicorns. From the point where it struck, a wall of magic blossomed outward until it encompassed the entire castle.
Celestia frowned before taking to the air. "Don't think this is over, Sombra! You can't say 'no' forever!"
"Yeah, we'll be back!" Luna added, as she followed her sister into the sky.
"They're headed towards Ponyville!" Applejack cried and she raced towards the door.
The others turned to leave and chase after the alicorns as well, when their host spoke up. "Indeed, a more wretched hive of scum and villainy has never been seen. Unfortunately, with the Castle of the Two Sisters so near, there is little my guards can do about its corruption."
"Oh, right. We're evil in this world, ain't we?" Applejack said. "Ah suppose that means all our friends and family are, too, huh?"
"I'm afraid so," the king replied. "I'm sorry to have put you all in this position, but hopefully this will all be over soon and you can return home. Follow me to my study. Hopefully, something there might assist you in overcoming those two. I've been recording all of the similarities and differences between our worlds with the help of my dear, sweet Celestia."
The ponies following him suddenly ground to a halt.
"Your..." Pinkie Pie started surprise.
"...dear..." Applejack continued dumbfoundedly.
"...sweet..." Rarity went on in a stunned whisper.
"...Celestia!?" Twilight finished in shock.
"...I think I am about to be violently ill," 'Black Knight' muttered to himself, looking decidedly queasy.
"Yes," the king replied, seemingly unaware of their reactions. "I fell for her the moment I laid eyes upon her beauty, and our love has only grown over the thousand years since."
Once everypony had calmed down, they had made their way to the king's study. The walls were covered with pictures and notes, and Twilight immediately borrowed parchment and quill so that she could take notes of her own.
"When your Luna had the darkness driven from her heart, ours embraced it," King Sombra explained. "Things have gotten worse so quickly that it's been hard to wrap my head around it. Now I have Sir Discord defending the north against attacks from Empress Cadance and the Crystal Empire, while Lady Chrysalis guards the lands to the south. I've been alone in defending Canterlot and the surrounding areas."
"Sir Discord!?" Rainbow Dash echoed in surprise.
"Lady Chrysalis!?" Rarity said, as well.
"I think it's best not to think too hard about all this," Fluttershy said, the king obviously not the only one having trouble wrapping his head around things.
Noticing Twilight furiously scribbling away at the parchment, 'Black Knight' leaned over to her and whispered, "I would agree with the timid one on this. Overthinking inter-dimensional inconsistencies is a swift road to madness."
Twilight hesitated before protesting, "But... but... what if this world doesn't make one hundred percent sense!? I need to record it all for posterity!"
"Our world doesn't make sense!" Pinkie Pie interrupted. "Why should this one? Who needs continuity?"
"Besides, there will always be time for this later," Black Knight added.
Sighing, Twilight reluctantly laid down the quill and parchment. "I suppose you're right. We do have more important things to worry about.
"So, King Sombra," Rarity said, "why don't you tell us about the first time you met our dear princess."
"Oh! I... you don't want to hear about that," the monarch replied in embarrassment.
"Oh, but I do!" The unicorn responded eagerly.
"Oh yes, please!" Fluttershy joined in with a level of exuberance unusual for her. "Tell us!"
"Well, it was a long time ago," the king began. "Long before any of you were born..."
"Even Fluttershy? Wow, that is a long time ago!" Pinkie Pie commented, drawing a glare from the pegasus in question.
"More mushy stuff, blegh," Rainbow Dash muttered, but made no move to leave as the story continued.
Applejack's attention was elsewhere. Ever since they had reached the throne room, uncertainty had been gnawing at her. 'A similarity's one thing, but who's gonna mistake somepony else for themselves?' The young mare thought. Turning away from the king, she looking towards his double... only to see the door closing behind him as Black Knight and Twilight left the room. 'That's it! Ah'm getting to the bottom of this one way or another! If he is Sombra, and he's got Twilight under some kinda spell, Ah ain't letting that stand a moment longer. And if Twilight ain't hypnotized or anything... well, Ah'll cross that bridge when I get there. Still, no point in worrying the others if Ah'm wrong.'
Making sure the rest of her friends were focused on King Sombra's story, Applejack slipped out the door after the pair.
"Are you okay?" Twilight asked, as she left the castle alongside her world's version of Sombra. "You've been acting a bit odd lately."
"Just dealing with old grudges and new revelations," the stallion replied. "...And what is it with goodhearted royal stallions and shield magic?"
Twilight shrugged and they walked in silence for a moment. Then she grinned and said, "I like the idea of dealing with the Evil Celestia and Luna without putting my friends in danger - I mean, that's why I learned Dark Magic in the first place - but you just wanted an excuse to avoid listening to him going on about the other Celestia, didn't you?"
"Can you blame me? I feel ill just thinking about it," he replied. "Between that and your friends..."
"What do you mean?" Twilight asked in confusion. "What about them?"
"They called me their friend. ME," Sombra went on. Seeing Twilight still looking confused, he added, "You read my journal..."
Twilight's eyes widened in realization. "Oh. Right. I supposed having your only friend abandon you when you needed them, would make you wary of others calling you a friend." Twilight smiled as she went on, "But you saw how they reacted when I started using Dark Magic. Sure they were worried, but they stood by me. Just give them a chance."
"It is the opposite that is the issue," the former tyrant said. "If they find out who I really am, an evil king who enslaved an empire, will they give me a chance? Should they?"
"That's a darn good question, now ain't it?"
The pair turned around in surprise to see Applejack standing behind them.