Back in Equestria:
There is a very special and important wedding going on. The wedding of Princess Mi Amore Cadenza and Shining Armor. The trouble is that Twilight Sparkle finds out that the one who is marrying her brother is a fake and the imposter sends her to the caverns where the real one is. So they both raced together to reach the wedding hall before it's too late. Little does Twilight know is that the imposter is also responsible for a another crime that has taken place in Canterlot before.
In the Wedding Hall:
The imposter princess and Shining Armor are about to be announced husband and wife and everypony is very excited for the wedding ceremony.
Princess Celestia announces, "Princess Cadance and Shining Armor, it is my great pleasure to pronounce you…"
But before Princess Celestia can finish the announcement, she hear a familiar voice screams.
The familiar voice screams, "Stop!"
Everyone turns to the door of the wedding hall to see Twilight Sparkle with a serious and determined look on her face. Her friends are kind of annoyed at Twilight because she accused Princess Cadence to be evil and controlling her brother. They believe she is trying to ruin her brother's wedding, but they are going to see just how wrong they really are.
The imposter says with frustration, "Ugh! Why does she have to be so possessive of her brother?"
She then notice that Princess Celestia hears her and know she needs to make an excuse before she finds out.
She makes fake tears and upsetly says, "Why does she have to ruin my special day?"
Just then someone says, "Because it's not your special day! It's mine!"
The pony who announces is none other than Princess Mi Amore Cadenza or who her friends calls her by Princess Cadence. Everyone in the room gasps with a shock to see that there are two Princess and bride to be in the same room at the same time.
The imposter shockley and angrily says, "What? But how did you escape my bridesmaids?"
Twilight and the real Princess Cadence look at each other with a smug look on their faces. They remember the original bridesmaids, Lyra Heartstrings, Lemon Hearts and, Minuette are under the imposter's spell. They don't know what to do with them, until Princess Cadence has an idea. She use her magic to bring a bouquet of flowers in front of them. Just then Princess Cadence throws the bouquet a ways and with that the bridesmaids chase after it.
They run after the bouquet of flowers and screams, "I want it!"
The imposter makes an evil look on her face and says, "Hmph. Clever. But you're still too late."
Applejack confusedly asks, "I… I don't understand. How can there be two of 'em?"
Then Princess Cadence makes a serious look on her face and angrily announces, "She's a changeling. She takes the form of somepony you love and gains power by feeding off your love for them."
The imposter is so made that she lights her horn up green and her eyes starts to glow green. She then use her magic to create a circle of green flame around her and it creates a field that causes her to change the imposter to her true form. Everyone is shocked to see the kind of pony the imposter is really is.
Her hoofs become black with holes on it, her pink with shade of purple wings becomes bluish green transparent wings, and her horn becomes a jagged like and her true form has finally been shown to everypony in the wedding hall. Everyone is comely shocked and scared to see the kind of pony she really is. The imposter is actually Queen Chrysalis ruler of the changeling and master of shapeshifters.
Queen Chrysalis evilly says, "Right you are, Princess. And as queen of the changelings, it is up to me to find food for my subjects."
As the changeling queen walk towards Princess Cadence, she evilly says, "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 of!"
Princess Cadence angrily says, "They'll never get the chance! Shining Armor's protection spell will keep them from ever even reaching us!"
Queen Chrysalis chuckles with an malicious look on her face.
Then says, "Oh, I doubt that."
"The changeling queen then turns her head back to where Shining Armor is.
She then use her horn to control him and evilly asks, "Isn't that right, dear?"
Shining Armor obeys Queen Chrysalis control, so he nods his head and says, "Mm-hmm."
Princess Cadence starts to get angrily that Queen Chrysalis is controlling her love, so she decides to run towards him as fast as possible. But she is stopped when Queen Chrysalis gets between her and her love.
Queen Chrysalis says as she lights up her horn, "Ah, ah, ah. Don't want to go back to the caves, now do you?"
Princess Cadence steps back a little with a serious look on her face. Twilight comes to her and she is angrily as Cadence is.
Then Queen Chrysalis explains, "Ever since I took your place, I've been feeding off Shining Armor's love for you. Every moment he grows weaker and so does his spell. Even now, my minions are chipping away at it."
Queen Chrysalis walk over to Shining Armor and put her hoof under his chin and says, "He may not be my husband, but he is under my total control now."
She then walk over to Princess Cadence and Twilight and screams, "And I'm sorry to say, unable to perform his duties as captain of the Royal Guard."
Everypony in the room gasps with horror after what Queen Chrysalis is saying, especially for Princess Cadence.
Princess Cadence horribly screams, "Not my Shining Armor!"
"Soon, my changeling army will break through. First, we take Canterlot. And then, all of Equestria!" Queen Chrysalis announce loudly and proud of it.
Then Twilight angrily screams, "That will not happen!"
Queen Chrysalis groans with annoyance and says, "You know Twilight, you're that much of a pest as the last pony who interfered with my plans."
"What do you mean?" Twilight angrily asks.
"Well…" Queen Chrysalis is about to say something.
But before she can say anything, she starts to laugh maniacally. Everyone are kind of confused and are kind of cared when she says something about another pony interfered with her plans.
"I don't want brag, but I guess it will be a good time to brag about it…" Queen Chrysalis evilly replies.
She then turn to Princess Celestia with a evil grin on her face and says, "Especially to you Celestia."
Princess Celestia is shocked that the pony Queen Chrysalis is talking about is has something to do with her. She is starting to be a bad feeling about it and worried what Queen Chrysalis is about to reveal.
Princess Celestia nervously asks, "Wh-what do you mean?"
Queen Chrysalis then decides to announces what she is talking about.
She then says, "You see many years ago, I was planning on taking your place to help feed my changelings, but then this unicorn mare saw me so I have no choice but to flee. But before I go, I'd made sure she never tells anyone and you what…"
"I had no idea that pony of your meant so much to you," Queen Chrysalis adds with a smirk on her face.
Princess Celestia is frighten yet confused on what Queen Chrysalis is talking about, "What do you mean that much to me?"
Queen Chrysalis laughs maniacally and says, "I wouldn't be surprised that you are feeling skeptic. After all, you never knew how the incident in your castle got started to begin with."
Everyone are starting to get frighten and confused of what the changeling queen is talking about. Twilight on the other hoof is the one who is very confused and yet is kind of interested to what Queen Chrysalis is talking about.
Twilight says in her thought. "What incident in Princess Celestia's castle is she talking about. The only incident that happened in Princess Celestia's castle is the fire in the throne room where…"
Just then Twilight's eyes widen with horror and realizes what incident is the changeling queen is talking about. She is more shocked to find out how much pain and sadness that Princess Celestia' and the victim's family been through.
Twilight quietly says with horrors, "She… she didn't."
Princess Cadence hear's Twilight talking in fear and she can see that Twilight is shocked and looks fearful about something.
Princess Cadence worriedly asks, "Twilight, are you alright."
Spike, Princess Celestia, and her friends notice that Twilight is looking very pale and are wonder what is wrong with her.
Spike walks over to Twilight to see what is the matter, despite that this might not be a good time to ask.
When Spike reaches her, he asks, "Twilight are you okay? You look like you've seen a ghost."
Twilight snaps out of her paleness so she can answer Spike's question.
Twilight scaredly says, "No Spike. I don't feel fine at all. I… I just realizes what incident that she's talking about."
"You do?" Princess Cadence says looking confused.
Queen Chrysalis hears what Twilight says and can tell that what Twilight is going to says will shock the ponies of Canterlot.
Queen Chrysalis makes an evil smirk on her face and says, "So you know what incident. Then it will be find to tell them what I'm talking about."
Twilight is to nervous and worried on how the ponies are going to react, but she knows that this is one mystery that the truth needs to be known.
Twilight gulps nervously and says, "It's… it's the fire that took place in the castle throne room.
Cadence shockley says, "But… but Twilight, nopony knows how it got started, how can you be sure Queen Chrysalis is talking about that one,"
Twilight turns to Cadence and answers, "Because it's the only incident that Canterlot ever faced that was never solved. Like Queen Chrysalis said somepony interfered with her plans and there was one one who was in the throne room during the incident occurred.
Everypony are starting to whisper to themselves about the incident that tooken placed years ago and wonder if what's Twilight saying is true or not. Spike remembers Princess Celestia and Twilight telling her what happened to the castle throne room and the pony who many believe have died in there. Spike is starting to believe that Twilight's theory is true and shocked to see who is the pony who stopped Chrysalis with her last plans.
Spike panicky asks, "Are you saying the pony who interfered with Queen Chrysalis' plans was Sunset Shimmer?"
"Yes. Pony investigators found her necklace but never the actual body and she was the only one who was in there, but now turns out there were two ponies when the incident occurred." Twilight explains sounding scared.
"So here's my question Queen Chrysalis," Twilight says as she turns to face Queen Chrysalis with a serious look on her face.
Chrysalis seems kind of impressed by Twilight's detective work, but she's annoyed to see that not one but two has set her plans on the wrong track.
Then Twilight's asks with a serious look, "Are you the one responsible for the fire in the throne room and responsible for Sunset Shimmer's death?"
Everypony is looking very scared and looking at Queen Chrysalis waiting for the answer. Princess Celestia is shock about know what has become of her old student and somepony she also consider a close friend.
"It's true I was the one who started the fire. I was hoping to create a small distraction, but that medding pony decided to walk around the castle went to the throne room and saw me doing my work, so I have no choice but to fled. But…" Queen Chrysalis explains with an evil look on her face, but stop as she is continues her confession.
She then makes an evil smile and says, "I also had great pleasure of sending that prized student of Celestia's to flames."
Everyone gasps with horror hearing what the changeling queen is saying, but the one who heart is starting to fall apart is Princess Celestia. Princess Celestia realized what Queen Chrysalis is saying, she's the one who started the fire in the throne room years ago and worst of all she's the reason why Sunset Shimmer is gone forever.
In her thoughts, Princess Celestia horribly says, "She… she's the reason why Sunset is gone."
Twilight and Princess Cadence can see that Princess Celestia is becoming very broken hearted when she hears about what really happened to her old student. They both know that her old student has disappeared after the fire in the throne room, but now they realized that Sunset is gone because of Queen Chrysalis.
Twilight says in her though, "How… how could she?"
Queen Chrysalis doesn't care of the fear in the room and says, "Now if you excuse me, my changelings need to be fed."
But before she can leave, Princess Celestia angrily says, "No. You won't."
Queen Chrysalis looks at Princess Celestia with a serious look on her face. Everyone can see that she has sadness and anger in her eyes. Not only that Queen Chrysalis takes the form of her niece, but she is trying to feed on her subjects, and the reason why she lost one and almost lost another .
Then Princess Celestia serious says, "You may have made it impossible for Shining Armor to perform his spell, but now that you have so foolishly revealed your true self…"
Just then Princess Celestia and Queen Chrysalis charge at each other with their horns connected.
Then Celestia says, "I can protect my subjects…"
"From you!" Celestia adds as she flies high in the room and launches a magical beam from her horn.
As Princess Celestia launches her magic, all she can think about is the good time she has with Sunset before she's been taken from everypony who loved her.
Princess Celestia says in her thoughts, "Don't worry Sunset, I promise I will avenge you."
Queen Chrysalis tries to be strong and withstand Celestia's magic. She then use more of her magic and it's starting to interact with Celestia's. At that moment, Chrysalis' magic has become too much for Princess Celestia.
The changeling queen's magic is so strong, that her magic blasts Celestia's horn and cause her to hit the ground hard and cause her crown to fall off. Everypony in the room gasps with horror that Princess Celestia has been beaten by the changeling queen.
Twilight horror screams, "Princess Celestia!" and runs towards her to see if she's okay.
Queen Chrysalis can see that her magic has become stronger. She knows the reason why and says, "Ah! Shining Armor's love for you is even stronger than I thought! Consuming it has made me even more powerful than Celestia!"
Back to where Celestia has fallen, Twilight and her friends are with her to see if she's okay. They can see that the tip of her horn has been burned a little from the blast.
Celestia is able to regain consciousness and says, "The Elements of Harmony. You must get to them and use their power to defeat the queen."
Twilight and her friends nod their head in reply. Excluding Twilight, and Rarity, Applejack and the others remove their bridesmaids dresses and run to get to the elements. Rarity who is still in the alter, catching the dresses that are falling and trying to make sure they're not dirty.
Twilight and the others call out loud, "Rarity!"
Rarity sighs in defeat and takes off her own dress. Then she dashes to where her friends are to get to the elements of Harmony.
Queen Chrysalis can see Twilight and her friends running for their live to reach the element.
Before they are gone, Queen Chrysalis announces to them, "You can run, but you can't hide!"
Back to where Celestia is, she has become paralyzed after hitting the ground she can't move but she is able to think about how everything she has witnessed. She feels very useless right now that she can't help her subject. She feels very upset that she ends up finding out the truth about Sunset Shimmer's death.
In her though Celestia sadly says, "I… I'm… sorry… Sunset. I'm… so… sorry."
Then then closes her eyes and passed out because of the fall and the pressure she is having right now. She isn't seeing that she is being put inside of a changeling cocoon but Queen Chrysalis and her changelings, so she can't escape that that it's possible. All she can do is feel sad that she ends up losing so much already and hoping that Twilight and her friends will save Equestria.