The fact Sombra was able to get rid of his cuffs like it was nothing caused Celestia and Luna to position themselves and the former said:

“You still have your magic!”

“But of course” Sombra replied. “How else would I be able to carry on my plan?”

“I knew it!” Rainbow Dash exclaimed, as she and the others also positioned themselves. “I knew this was all an evil plan!”

“Kudos for you, rainbow head” Sombra said, sarcastically. “Although you can’t say it was for smarts, but rather for stubbornness.”

“I can’t believe it…” Twilight said, completely shocked. “You… You really…”

Seeing Twilight look at him with shock and disappointment on her eyes really pained Sombra’s heart. Perhaps he could reach to her without executing his plan.

“Twilight, please, let me explain…” Sombra said, while trying to touch Twilight’s face.

But she moved away his hoof and asked:

“So, all of this… was a lie?”

“No, not everything” Sombra replied. “Perhaps, in the beginning, I planned to charm you and use you in my plan, but… I truly came to fall in love with you. You are, without a doubt, the best thing that ever happened to me.”

“Please, can you stop with all the lies?!” Rainbow asked. “It’s making me sick!”

“Ah have tah agree with Rainbow, here” Applejack said. “Ya can’t fool us anymore, Sombra.”

“Why, can’t a villain also fall in love?” Sombra asked. “Don’t tell me only heroes can find love?”

Turning again to Twilight and said:

“Please, Twilight, let us just go… together. We can have everything we want.”

But Twilight, despite all her love for Sombra, couldn’t ignore the fact that he had lied to her in the worst possible way. She stepped away from him and said:

“I’m sorry…”

Despite that rejection, Sombra was unable to get mad at her.

“You know, Twilight, you always surprise me of how genuine you are” he said. “I guess that’s one of the reasons why I love you. It would appear we’re doing this, isn’t it?”

“Guards, seize Sombra now!” Celestia commanded.

However, the guards did nothing.

“Haven’t you heard my sister?” Luna asked them. “Seize him!”

But the guards just positioned themselves a little ahead of Sombra, as if trying to shield him. That attitude really shocked everypony and Sombra chuckled and said:

“It would appear they have second throughts. I can see that your confused. But then again, you should have foreseen this. Do you really think I was just hanging around pretending to a goody two-shoes? No… I’ve been busy preparing everything for the big reveal. These guards, along with all the others you have sent to watch over me, are now loyal to me… And by quite some time, actually… ever since I got my hooves onto this.”

And he made his book appear.

“Your book!” Celestia exclaimed. “But I thought…”

“You should have hidden it better, Celestia” Sombra taunted. “It was not very hard to find it. But then again, it emanates such dark energy, I could feel it miles away. With it, I was able to turn your precious guards into my servants. Take a peek.”

And the doors burst opened and all the guards appeared, all with red eyes and a dark colored coat. The sigh was so horrible that Fluttershy took her look away from them and Spike went to shield himself behind his throne. Even confident ponies like Applejack got chills just seeing them.

“Oh, that’s the most unfriendly looking group of ponies I’ve ever seen” Pinkie Pie commented.

“Please, as if they scare me” Rainbow Dash said. “You’ll see what I’ll do your…”

But before she could finish, Applejack pushed her tail to get her down and then covered her mouth with her hoof, whispering:

“Do ya want tah make dah evil powerful villain even angrier?”

“You have gone too far, Sombra” Celestia said. “How could you have turned these innocent ponies into your slaves? They had nothing to do with this.”

“Once you put them guard me, they start having it” Sombra replied. “Besides, they were standing on my way… and also I needed some help. Now, it’s time to get… well, everything!”

“No, Sombra” Twilight said. “I won’t let you.”

“I think you mean we won’t let him” Rainbow Dash said, as she and the others stood beside Twilight.

“Thank you, girls” Twilight said, smiling. “And… I’m sorry for dismissing all your suspicions, Rainbow.”

“It’s okay, Twilight” Rainbow Dash said. “Now you know the truth and we can’t stop him now.”

“But how are we going to do it?” Rarity asked. “We don’t have the Elements with us.”

That was a very good question. King Sombra’s dark magic was extremely powerful, even more when he had the help of his new underlings. But then Twilight noticed the map, at the center of the thrones. It was connected to the power of the Tree of Harmony, along with all the castle. If she could harvest the power of the map, maybe she could connect herself to the Tree of Harmony and get the power of the Elements of Harmony.

And so, she flapped her wings, flying and landing over the table, and said:

“Your evil plan, whatever it is, ends here, Sombra.”

Seeing her like that made Sombra realize she had finally realize how to access the power of the Elements of Harmony… and that was something he was counting on.

Twilight charged her horn with magic and then tried to access to the power of the map. The table started to shine with an intense light that elevated Twilight. She then was surrounded by a ball of light that casted five beams that hit all of her friends, also elevating them and surrounding them in a ball of light as well. After the light released them, the six ponies were transformed in the same forms they got when they defeated.

Seeing that, Sombra got amazed for all the power he was seeing. It was really amazing.

“Magnificent…” he said. “So this is power of the Tree of Harmony…”

“Son’t you worry, my king, we’ll protect you” the guards told him, as they positioned themselves in front of Sombra.

“What are you doing, you fools?!” he shouted. “Get out of the way! Go wait for me at the place we talked about!”

“But, my king…”

“NOW!”

And so the guards got out, leaving King Sombra to deal with Twilight and her friends all by himself.

“This is your end, Sombra” Twilight told him.

“If you say so, my love” Sombra replied. “Come on, try to destroy me. I can’t way to see if you can really do it.”

Twilight prepared to do it, but she had a slight hesitation. After all, despite the betrayal and deception, she still loved Sombra. There was still a part of her that didn’t want to hurt him, but her duty to her friends made her decide she had to do it. And so she casted a rainbow beam against Sombra that started to go around him.

The attack stopped and the six mares landed on the floor, confident that they had been able to do it. Celestia and Luna seemed also relieved.

“Ah, all right!” Spike exclaiming, coming out of his hideout. “Eat that, Sombra!”

However, to the shock of everypony, things had not gone as they have expected. The rainbow that was involving Sombra soon became as black as the night, with the pure magic of the Elements of Harmony turning dark and being absorbed by King Sombra, with him laughing evily after that.

“Okay, I… I’m going to hide again, if you don’t mind” Spike said, returning to hide behind his throne.

“What… just… happened?!” Rainbow Dash asked. “I thought we had him!”

“Twilight, what happen’d?” Applejack asked the young alicorn princess.

“I don’t know…” she said. “I used the full power of the Elements… I… I don’t understand!”

“Sombra… what did you do?” Celestia asked the dark unicorn king.

He chuckled and then said:

“Let’s just said building an army wasn’t the only thing I’ve been doing. I realized that the only reason why you’d be able to defeat all of your enemies was because of the Elements of Harmony, so I made sure that at the time you would use it against me, that, not only would not work, but that power would be transferred… to me.”

And he laughed, while he was surrounded by an intense dark energy. Twilight and her friends got shocked by that revelation. Reacting to that, Celestia and Luna advanced to attack Sombra.

“Princess Celestia! Princess Luna!” Twilight called, worried about what Sombra could do to them.

“Really?” Sombra asked them, before casting a powerful dark beam against them.

The two then find themselves be engulfed by the dark magic, before they were turned into stone.

“NO!” Twilight shouted, while her friends gasped in horror.

Sombra laughed and then said to the petrified princesses:

“I presume you two get to know how Discord felt when you turned him into stone. I bet he would appreciate the sweet irony, even if now is not as I remembered him.”

“You will pay for this!” Rainbow Dash shouted, trying to go against Sombra before being stopped by Applejack.

“Don’t worry, girls, we can free them using the power of the Elements of Harmony” Twilight said.

“Can you, now?” Sombra asked, sarcastically. “Well, perhaps, you could… if I allowed it.”

“Well, then we just have to pass through you” Twilight said, charging her horn.

“Now you’re talking…” Rainbow Dash said, while stretching his limbs.

“We’re ready when you are, Twilight” Applejack replied, preparing his hidelegs.

“Yeah, I already have a party cannon loaded for battle” Pinkie Pie said, while getting her party cannon.

“Well, fighting isn’t exactly my style… but I will get my hooves dirty if necessary to take this bandit down” Rarity said.

“You… you can count on me too” Fluttershy said.

Twilight smile at her friends, grateful for her dedication and undying friendship. However, there was a wave of darkness that blow away Twilight’s friends, including Spike, causing them to hit the hall and be restrained by dark crystal. Twilight turned around and saw it was Sombra who did that.

“Release them, Sombra” Twilight demanded, while intensifying the magic around her horn.

Sombra used his shadow transformation to appeared right in front of Twilight and said:

“Oh, my dear Twily… That determined look you have now… It only makes you even more… attractive. But there’s one thing you don’t know…”

Approaching his muzzle to her ear, he whispered, in a similar manner he used to do when they were together:

“You… can’t… hurt… me.”

It was then Twilight noticed he was right. Despite her desire to put an end on Sombra, she just couldn’t do it.

“What…?” Twilight asked, not understanding what was happening.

As if her body had a will of its own, Twilight cancelled the transformation, what caused her friends to return back to normal as well.

“Twilight… what’s going on?” Applejack asked.

But she didn’t answer, as not even her knew what was going on.

“How did you…?” Twilight started to ask.

“How did I did that?” Sombra asked. “Well, how do you think? I had to make sure the magic of the Elements of Harmony didn’t destroy me once I tried to absorb them. After all, they are pure magic. And since your element is the heart of their power, you were the key to everything. And once I had my book, I was able to find the right spell that would allow me to get all of the Elements’ power without being overwhelmed by it: the Love Curse.”

“The… Love Curse?” Twilight asked.

“An ancient and powerful curse” Sombra told. “When casted, it prevents the victim from hurting the one they love… even if that someone is an enemy. I casted on your element not so long ago and it activated once you summoned its power.”

“So that’s why…” Twilight started. “You made me fall in love with you… so I would be cursed to not harm you?”

“Yes” Sombra confirmed. “Ingenious, right? I used one of the greatest forces of goodness in my advantage… Now that’s how it is done.”

“Then my friends were right…” Twilight said, with tears on her eyes. “Everything was a lie.”

“Well, that’s just it…” Sombra replied, approaching Twilight and putting his hoof over her face. “My love for you is real.”

“Yeah, right, as if that was true after what you just said about…” Rainbow Dash started.

But before she could finish, Sombra made a gesture and crystal formed around Twilight’s friends muzzles, preventing them from speaking.

“I should have done that long ago” he said.

“How can you say your love for me is real when you cursed me?” Twilight asked. “How do you expect me to believe in what you’re saying, when the only things you’ve been doing this all time was deceiving and plotting?”

“When I started my plan, my only goal was to take the power of the Elements of Harmony” Sombra told. “For that, I needed the Love Curse. But for the curse to be successful, I needed that my target felt real love for me. That’s why I started to court you. But then… After our first kiss… Let’s just say I started to feel something. It was only after our first night that I realized what it was: love. Believe me, I tried to struggle it, but I couldn’t do it… However, that would represent a problem. Once I enacted my plan, despite being granted an immense power and immunity to the Elements of Harmony’s magic, I would lose you… Fortunately, I got to meet somepony that give me a little help.”

“Somepony…?” Twilight asked. “Who?”

“Let’s just say that your ability to make great friends is only matched by your ability to make great enemies” Sombra replied. “Anyway, thanks to that pony, my curse was reformulated and now, not only you can’t hurt me, but you’re also bond to me.”

“What do you mean with that?” Twilight asked, terrified to know the answer.

“It means now my mere absence can cause you pain” Sombra told. “You need me… as much as I need you.”

Hearing that, Twilight couldn’t feel more disgusted.

“No…” she said, with tears coming to her eyes. “No… You… You enslaved me…”

“No…” Sombra said. “This is not slavery. I just can’t lose you. And I won’t. I did what I have to do to not lose the mare I love. We were meant to be, Twilight. You know that…”

He tried to touch her face again, but when he was about to do it, she grabbed his hoof with hers and said:

“I won’t let you do this…”

“You can try to fight it, but you won’t be able to do it” Sombra said. “Why don’t you try it?”

Indeed Twilight tried to fight what she was feeling at that moment. She tried to move Sombra away from her, to push him back with all the power she had. However, when she went to do it, she felt something holding her back, making her want to get Sombra only closer to her. And so, she moved Sombra’s hoof to her face, feeling his touch that was able to sooth her. Sombra smiled and then proceeded to give her a kiss on the lips, asking then:

“Do you see it now? You need me. But don’t worry, from now on, we’ll be together… forever.”

“Please, Sombra…” Twilight cried. “Don’t do this to me.”

“Don’t wet this beautiful face with those tears, my love” Sombra said. “You’ll see everything will be okay. Now you may feel I’m being cruel, but you’ll see this was for the best. I’ll tell you what, if you come with me now, I’ll spare your friends… I’ll even release Celestia and Luna from their stone prisons.”

“You… You mean that?”

“It’s a promise.”

Despite Twilight had lost trust on Sombra, the fact is she couldn’t help but notice he was telling the truth. She looked to Princess Celestia and Princess Luna petrified and then to her subdued friends. They all were shaking their heads, while trying to talk. They probably were trying to dissuade Twilight to not accept Sombra’s offer. However, she only wanted for her friends to be safe, as now she couldn’t escape Sombra.

“Let’s go” she said.

Sombra smiled and then said, while opening his cape and covering Twilight’s back with it:

“As you wish, my love…”

And the two disappeared in a wave of darkness. As soon they were gone, the crystal holding Twilight’s friends broke and they were release, while the stone covering Celestia and Luna’s bodies cracked and broke, releasing them.

“No, Twilight!” Celestia shouted, but too late…

The End…?