Reverse Nightmare

Twilight opened the door to Tia's cell using her magic, Celestia was battered and bruised from all the beatings her former students did to her it didn't matter though she was going to die anyway. Even her faithful student Twilight who has been through everything with Celestia now was under Luna's control as was everypony else, they were all against her now. Nightmare Moon walked over to Twilight and said "We are ready for her, you can bring out our accuser Celestia to be burned at the stake." Twilight used her magic to pull Tia towards her and Celestia had empty eyes that told a story like no other but this time it was going to be Nightmare Moon ruling all of Equestria and Tia was going to burn.

Everypony was standing saying in unison "Burn Celestia!" Over and over they said it, the looks Tia got from the ponies that would call her princess was now hated by all and watching from the rooftops a little filly with curly purple hair "No...not Celestia, I've have to stop them!" Sweetie Belle jumped from the rooftop and landed in front of Twilight and her friends "Stop this! This isn't right!" said Sweetie in protest. Twilight responded harshly "Get out of my way you little pest!" Sweetie stood her ground but her own sister Rarity levitated Belle to the other side while Rainbow Dash and Applejack held her back while they burned Princess Celestia burning at the stake. "NO!" cried out Sweetie but her screams were drowned out by everypony's cheering. Sweetie Belle tried to escape but Applejack kept a strong grip on her making her watch Celestia become nothing more than ashes and bones in front of Sweetie.

Rarity and Applejack released Sweetie Belle who ran up to what was left of Celestia considering that the ashes were all that was left of the princess of the sun. "You monster! Your just a stupid moron that is jealous of your now dead sister!" said Sweetie Belle angry and crying at the same time. Nightmare Moon slapped her in the face then said "Know your place little one. If you could understand..." She let out a loud laugh which made Sweetie's ears hurt, the shriek caused her to fall on to the ground in pain.  This was the chance to get Dash and Pinkie to take Sweetie Belle away from Equestria's new ruler Nightmare Moon, Belle did not want to leave but was forced into the dungeon below Ponyville.

Rainbow Dash threw her into her cell by herself with no escape in sight. "Your not getting out of here alive so Sweetie so be a good little filly and stay out of our business." said Dash and Sweetie had revenge on her mind but how was she going to do that? She was in a cage with no chance of escaping, then she heard Tia's voice in her head "Sweetie you there?"Sweetie thought she was losing her mind but it was Princess Celestia, "Princess? What are you doing in my head?" The spirit of Celestia appeared in front of her like a ghost returning back to life.

"Sweetie I want you to take revenge for my murder, I want you to kill Nightmare Moon." said Celestia proudly and a sinister smirk spread across Sweetie Belle's face as she let Tia enter her body, she felt a power she never felt before it could be only be done by the one and only Princess Celestia. Sweetie's eyes turned into a very bright green as if she was possessed by a spirit and she was but this one wanted revenge.

This is for you Celestia, I'll kill anyone that gets in my way! thought Sweetie who gave an ominous but terrifying laugh.

If Nightmare Moon wasn't scared of her now she was going to be very soon.