As the preparations for the wedding passed, what would have been just Spike toying around as Twilight and her friends made the preparations for the wedding ended up being him having to put up with the voice inside his head talking about how Cadence was being strange, that he shouldn't be trusting her, even accusing her of being dangerous. Normally, had this accusations come off from Twilight, which she did later that day, he would have just brush them off as her being over protective of her brother but this accusations coming from the voice were now being more mean, after all, how dare him to accuse Cadence of being suspicious when he didn't even know Cadence at all?
Sadly, during all that time, Spike was always making company to one of Twilight's friends, so he never got the chance to speak to that voice and finally tell him to shut up, something that he wanted to do more and more as it said things like "a princess wouldn't lie to her servants" or "a princess wouldn't look dirty her braids just because they disagreed with her" but he didn't have that chance and all he could do was to fake up his annoyance by playing with the wedding couple's toys.
That way, everything advanced until the next day, when the practice wedding was made and Twilight made quite a scene by accusing Cadence of being evil by making weak arguments that were easily brushed off by her brother. After that, Spike decided to leave Twilight alone because he wasn't quite sure what to tell to her and he was sure that she needed to think on what she did but that didn't stop the voice from saying "she gave weak premises, but she wasn't wrong about her being evil" at which Spike decided to go to his room, alone, making sure that nopony was watching him and finally talk with that voice.
As Spike was finally getting a private moment on his room, with the rest of the girls helping on the wedding. He decided to finally talk to that voice regarding what it said about Cadence and how "suspicious" she was being.
"Look!" - Said the young drake while pointing at the air. - "One thing is to be annoying in my body and a completely different one to accuse Cadence of being suspicious. She's a nice pony who wouldn't even harm a fly."
This time, the voice didn't take its time to answer, this time with a sense of urgency that wasn't quite normal from it.
"Kid, I understand that you may think that based on what you've told me and what you've seen but eyes can be deceiving and, trust me, she's not acting normally, even your mom noticed it or don't you find strange that the one pony that should know her the best doesn't trust her?"
Spike took a moment to think about it, after all it was true, Twilight has already stated why she didn't trust in Cadence but everypony blamed her behavior on the wedding planning increasing her nerves and, sure, Twilight did brought up some interesting points last night but she behaved horribly with Cadence and even called her evil and those accusations were plain wrong.
"Look" -. Responded an annoyed Spike. - "Twilight was just jelous, you'll see how she apologize to Cadence very soon."
With that said, Spike decided to go to the altar to search for Twilight and prove the voice that all of this was just paranoia but, as he got closer to the altar, he saw something that made him feel strange. Twilight was gone missing.
According to Cadence, Twilight decided to leave the wedding as a form of apology and that she would be seeing them back in Ponyville and all Spike could feel how the voice was telling him just how this was more and more suspicious for the one pony that said she was evil was now, suddenly, "leaving the wedding", which, as annoying as it was for Spike, there really wasn't much to argue against until he could find Twilight and prove the voice wrong, but that would be after the wedding.
That way, the wedding went on with Spike holding the rings and waiting until the wedding was over and the married couple would finally be together. It was a lovely sight, seeing the arrangements being used so well, the girls look fabulous, specially Rarity, the Cutie Mark Crusaders were doing a good job throwing the flowers, Cadence looked gorgeous, Shining Armor looked as well as a Stallion could look like, it looked like everything would go fine until Twilight appeared.
When Spike saw her, one part of him was relieved to see her but another part of him was feeling anxious because it didn't look like she was changing from her attitudes although Cadence's remark did caught his interest:
"Why does she has to be so possessive of her brother?!" - Now, it wasn't what she said what sounded strange, it was her tone of voice which, many noticed, was more dismissive and mean, contrary to the common neutral tone she was using so far in the wedding preparations and it became extremely suspicious when she suddenly changed her tone and modified her statement as she realized how strange she sounded herself, this time with more sobs. - "Why does she has to ruin my especial day?"
Thankfully for Spike, before the voice could even say anything, another voice erupted from the doors besides Twilight. Much to Spike's chagrin it was the pony he expected the least to see, for it only gave the voice the reason it was searching for.
"Because it's not your especial day" - Said Twilight as the other pony entered, this one being a pink alicorn with a disheveled mane, dirt all over her coat and looking, overall, as she has seen better days, it was none other, than Princess Cadence who decided to shout her affirmation, one that made very clear that Twilight, and the voice, was right all along. - "It's mine."
The whole room shouted in shock, seeing now two Princess Cadence, and letting very clear that something very wrong was going on here and it was all made even more clear as the Cadence besides Shining Armor claimed with an angry curiosity.
"What!?" - Anger and malice spewing from her snout. - "But how did you escape my brides maid!?"
The two ponies in the entrance looked at each other with a knowing look and explained how distraction was an underrated tool, making very clear that ingenuity was their forte.
"Clever" -. Said the fake Cadence. - "But you're still too late."
"But Ah' don't understand" -. Said Applejack as she made a legitimate question. - "But how can there be two of them?"
"The fake one can shape shift!"
Said the voice inside Spike's head and this was confirmed by the real Cadence.
"She's a Changeling! She takes the form of somepony you love and gain power by feeding from your love for them!"
As Princess Cadence was making her accusations, the Fake Cadence's eyes were glowing green as her face showed all the anger she could muster. Anger released in a huge green fire that surrounded her being, burning away her fake form and showing her true form to the rest of the audience.
Her true form was of one with an insect's wings filled with holes each wing, a black chitin covering her body with her extremities filled with holes as well, her horn being twisted in weird forms, a bluish mane with a hole in it, green eyes with cat like slits and a small crown on her head.
Spike, along the other ponies in the room were in shock as the changeling started to laugh, showing how confident it was at this moment.
"Right you all, princess" -. Her voice sounded distorted as if it was unable to hold a defined voice on herself. - "And is queen of the Changelings, it is me who has to find food for my subjects" -. She then started to move towards Cadence, the pink alicorn remaining as stoic as ever, and continued on her gloat while Spike was unable to move due to the shock. - "Equestria has more love than any place I've ever encountered, my fellow changelings will be able to devour so much of it that we will gain more power than we have ever dreamed on!"
Cadence decided to refute the Changeling Queen, her determination remaining as tall as ever.
"You will never succeed! Shining Armor's protection spell will keep them from ever reaching us."
The Changeling Queen laughed at her and simply responded.
"Oh, I doubt that" -. Her horn then started to glow green while she was looking back at Shining Armor. - "Isn't that right dear?"
The mind controlled stallion could only nod, his will clearly gone by now but, instead of depressing Cadence, all it did was making her run straight to him before the Queen's hoof stopped her as she made sure that Cadence wouldn't move again.
"Ah, ah. Don't want to return to the cave now, do you?"
Cadence simply stepped back, clearly too weak to face her. With that solved, the Changeling Queen went back to Shining Armor as she continued in her speech.
"All of this was to help me, I've been feeding from Shining Armor's love for you, every moment he grows weaker and so does his spell, even now my minions are cheeping away at it."
She said as she was looking up, clearly knowing what was going on right now.
As all of this was happening, the voice was trying to speak to Spike.
"Kid, listen, I know how to fix this..."
But Spike was more focused on what he was seeing rather than what he was being told right now.
The queen simply laughed, clearly winning so far, and continued as she put her hoof in Shining Armor's snout.
"He may not be my broom, but he's under my control now and unable to do his duties as captain of the Royal Guard."
"Not my Shining Armor!" - Said a Princess Cadence that was getting anguish as the situation developed in front of her. Meanwhile, the queen continued, her body now floating as her joy was increasing.
"Soon my changeling army will break through the shield and we will take Canterlot first and then all of Equestria-"
"No!" - Said a voice that has been remained in silence for enough time, now that she was completely aware of the danger her ponies were in, Princess Celestia decided to take cards into her hoof. Her tone being cold and menacing. - "You won't."
The changeling queen then lowered herself to the ground, now aware that there were still some issues that still had to be dealt with.
"You may have made it impossible for Shining Armor to perform his spell" -. Said Princess Celestia, confidence dripping in her voice. - "But now that you have foolishly revealed your true self" -. She then charged towards Chrysalis, the changeling queen responding back by charging to her as well. - "I can protect my subjects" -. Celestia then raised herself to the air and prepared a huge yellow spell against the queen. - "From you." - And she fired the spell towards the alien invader.
The changeling queen responded back with her own spell as well, making the two beams clash in a fight of wills that Celestia was winning at first but the Changeling Queen then started to put more energy into her attack, giving her an edge that took Celestia by surprise and knocked her out into the ground, making all the ponies watching fall into despair as their monarchic matriarch was unable to protect them.
Twilight and her friends quickly moved to Celestia's aide and see if she was fine while the changeling queen started to look at her horn with a huge amount of surprise.
"Ah, Shining Armor's love for you is even stronger than I thought" -. Said the queen that was realizing how much power she was actually capable of right there and then. - "Consuming him made me more powerful than Celestia!"
The six mares got close to the princess and heard her last words before falling unconscious.
"The Elements of Harmony, you must get to them and use their power to defeat the queen!"
The six mares looked at each other, understanding that their duty was calling them, took off their dresses and moved to the Elements of Harmony (ignoring how Rarity delayed them by making sure the dresses she made were fine) hoping to stop this nightmare before it was too late.
Meanwhile, the voice finally managed to get through Spike's shock.
"Kid, listen to me!" - Spike finally started to listen as he saw Cadence, Shining Armor, Princess Celestia and the changeling queen while trying to figure out what to do. - "Kid, listen" -. The voice continued. - "I know how to fix this but, first, you must make sure that everybody's fine. We can see for your mom and her friends later but I know that some fillies came here with you, right?"
Spike quickly moved his eyes and tried to find Applebloom, Sweetie Bell and Scootaloo, hoping they were fine, but they were nowhere to be found, making Spike listen even more to the voice.
"Kid, first make sure they're fine and then I'll tell you how to solve this, ok? Don't worry about the princesses, the queen won't harm them, trust me on this one, but there's no guarantee that those fillies will be fine."
Spike, for the first time in his life, decided to listen to the voice and went to search for the Cutie Mark Crusaders as Cadence was shouting his name and asking where he was going. All Spike could do was saying that he would go search and see if the fillies were ok before leaving the room that contained a fainted Celestia, a trapped Cadence, a mind controlled Shining Armor and a maniac Changeling Queen.
As Spike went through the castle, searching room by room for the fillies, his mind started to fill with fear over how dangerous the situation was and how helpless he felt over the idea of him being unable to do anything to stop these invaders.
For each room Spike would pass by, he would open the door and see if he could find the fillies but he couldn't find them. He was starting to feel as if he was going to fail again when, finally, after opening another room for the fifth time, he would hear a little gasp coming behind a small table on one side of the room.
"Apple Bloom? Is that you?"
He asked. A small female voice responded back with certain hints of fear on the call back.
"Stay away... we are very strong fillies and we can beat you should we want."
Spike quickly decided to easy their doubts.
"Don't worry girls, it's me, Spike, you have nothing to fear."
He was thinking that this would work but he was soon proved wrong by Sweetie Bell.
"How... how do we know you're not one of those things pretending to be Spike? Tell us something only Spike would know about."
Spike tried to quickly think something and decided to dig up on of his most well guarded secrets, hoping that it would allow them to trust in him, even if he almost whispers it.
"Well... I... kind of... like Rarity..."
He waited for a few seconds and, to his shame, he was responded by Scootaloo with a shocking revelation that he was wishing to be false.
"Ha! You can't fool us, everybody knows about Spike liking Rarity, so try something else or we will kick your flank."
There were some whispers he couldn't hear so well but that wasn't as important as trying to keep himself up after finding out that his secret wasn't so secret but none of that mattered as he started to hear one of the scariest sounds he ever heard on his life, it was the sound of a huge object in the sky was being shattered, its pieces falling down to the city and being followed by multiple crashing sounds into the ground, as if multiple heavy objects were thrown to the streets and, once Spike went to a close window to see what was that sound, he found that, as he guessed, the shield fell down and the changelings were now crashing down into Canterlot.
Spike's mind rushed with fear over the idea of those things taking Twilight and all the other girls but he knew that all he could focus for now was trying to keep the cutie mark crusaders safe, so he entered back into the room and closed the door.
"Ah! He's going to attack us!"
He heard Sweetie Bell talk but he soon tried to make sure they understood what kind of problem they were now getting into.
"No I won't, in fact, I'm trying to help you. The shield is down and they're invading the streets, we must close this door and hunker down while hoping they don't find us, understood?"
For a brief moment they didn't respond but the fillies quickly started to look up and saw how Spike was now trying to pick up a chair and put it on the door as if that would block it. They quickly followed suit and tried to block the door but that soon was found out to be useless as the door quickly started to shook for the force being inflicted on it, small cracks quickly appearing on the door, which forced Spike and the little girls to move a table to a corner and hunker down, hoping to last as long as they could.
Terror was filling up Spike's mind as he tried to think of a way out of this and found no solution to this but, before despair could get him, the voice once again decided to talk to him.
"Kid, listen, I can help you out of this problem but you must listen to me."
Spike was annoyed but, as desperation was creeping in, he found no other reason to avoid him.
"Alright, what is your idea?"
He ignored Apple Bloom's weird looks at him as the voice started to give him the solution for his problem.
"Look, I can easily beat this guys down if you just give me the possibility of it."
The door quickly busted, a hissing sound following it as a changeling quickly entered in the room. Spike was now listening closely and responded through whispers.
"Alright, how can you help me, what must I do."
And, as Apple Bloom was starting to ask Spike to whom he was talking to, the voice gave him a solution that made him feel fear on levels he never thought possible.
"Just give me your body. Allow me to take it over and I will get rid of these shape shifters before you realize it."
Spike was feeling wrong, as if making a deal that he shouldn't be doing, but the changeling wasn't giving him many alternatives.
"Alright" -. Said a trembling Spike. - "Just, please, get rid of them."
And, as Spike shut his eyes with fear and the changeling found them hiding behind the table while Apple Bloom was shaking him, thinking he was going insane, Spike's mouth suddenly formed a smile as his teeth sharpened and his voice became more mature.
"It's a deal then."
Spike then opened his eyes, no longer green emerald, and looked at the changeling that was now going to transform into his first victim on this fight.