Celestia instantly put on a firm mask as the guards rushed in. They all got into attention with Shining Armor in the front.
"Princess, the castle has been damaged greatly. The left wing of the castle slipped from it's support and fell a ways down the mountain. Search and rescue are at the site of the incident."
"Any casualities?"
A female soldier at the end piped up "None so far, your highness. 25 injured maids and guards were sent to the north medical wing."
"Shining Armor, where is Cadance. We have something to discuss that is of the most importance."
Cadance slid from behind the guards "Is it over... Auntie?"
Celestia looked grim and for the first time, frustrated. "Twilight..."
The lavender unicorn perked up and Nightmare blocked her. The black alicorn narrowed her eyes.
"You will not send these girls on this mission alone. It will kill them. Allow me to explain."
Shining Armor turned towards the guards "I want the hallways lined. The throne room soundproof. Complete lock down of the castle, any and all suspicious pony will be detained until further notice."
"Yessir!" They saluted before walking out in an orderly line and closing the door behind them. Not too long after, the walls were aligned with many maguc auras.
Nightmare lit her horn and in a flash, Chrysalis stood before them still shocked from the experience.
"Nightmare?"
The black alicorn's horn was still alit as she bathed the room in an illusion. A large door appeared that had many intricate and detailed designs.
"This is the Gate to Tartarus. I have only seen it once in my entire life. This has a very difficult puzzle on it that keeps it closed. A puzzle that only Celestia knows..." The white alicorn puffed up at the suggestion but said nothing.
"So this is what keeps the windigos in?" Twilight questioned looking deeply at the puzzle.
"In short, yes, it does, Twilight." Luna jumped in "I, just like Nightmare, have only seen it once in my life."
Nightmare nodded stiffly "The inside is mostly dark as it is the land of th- So Ah'm confused. What lives there that could kill us?" AppleJack interrupted.
Chrysalis glared rolling her eyes. "If you would put a muzzle on it, you'd know."
"Don't talk to my friend like that!" Rainbow Dash growled.
"Quiet, Everypony- erm... Everyone! Nightmare is informing us of the threat that just attacked us. From what I can hear, there's more than just the one that attacked us."
"It was strange like faded but it's magic was physical." Twilight explained.
Chrysalis hissed "My daughter is not an it...."
"Daughter?!" Everyone except Nightmare and Celestia exclaimed. Cadance looked pale as she hugged her enlarged stomach.
"Yes... My daughter was killed a long time ago by Celestia!" Everyone in the room looked at Celestia, who couldn't look even look at the changeling queen.
"That's why Auntie wanted your forgiveness..." Cadance muttered coming to a realization covering her mouth as her eyes watered.
Shining Armor pat her back but couldn't hold back the anger and disgust that assault his system. Disgust in his leader's murder of a foal. Anger at the changeling for the past. She'd controlled him and Twily but he couldn't find it in himself to remain angry for some reason. Was she truly justified in her actions?
Nightmare cleared her throat "Ignoring the bomb shell in the room, Tartarus is inhabited by everyone who has died. Ponies, Griffons, Minotaur, Dragons, etc. A Cerberus that guards the living from the dead and the dead from the living. And- Tirek!!!" Twilight yelled hyperventilating.
"Yes... Tirek."
"What if he gets loose again and I have to take all the alicorn magic, and we don't have the elements like before!" Twilight was feeling light-headed.
Nightmare was obviously confused by this statement "Tirek has been out of Tartarus?!"
"Yea, right around when Twilight became an alicorn..." Fluttershy squeaked "He took advantage of poor Discord and took everypony's magic."
"Is that what left it open...?" Nightmare questioned.
"Impossible. Tia checked it herself...." Her statement drifted off with wide eyes as everyone looked at Celestia, who was now on the hot seat.
"I assure you that I did not leave Tartarus open!"
"So it was open! And you decided to leave this information to yourself! I thought we were equal in power and, I deserve to know of any threats to our subjects!" Luna screamed at her getting red across her muzzle from anger.
Celestia teared up "Lulu, I- Save it, Sister. We will assist in neutralizing this threat." Luna then turned away, opening the throne room doors before leaving.
Nightmare was struck silent by the exchange. Twilight walked up to her mentor.
"I have to words.... I just-" Twilight ran away after Luna and was followed by her friends.
Cadance and Shining Armor announced that they would sleep on it before making a decision leaving Chrysalis and Nightmare with a sobbing solar princess.
Chrysalis was disgusted as Nightmare kneels down and wraps her wings around Celestia.
"Why are you still here?" Celestia hiccuped "I hurt everyone..."
"My dear sister...." Nightmare started "You must make up for your mistakes... I've been called imaginary. Cast away. Hurt emotionally and neglected physically."
Celestia eyes widened "Moon... I-I thought that you were a...."
Nightmare looked out into the night "In a way, I was..."
Chrysalis watched at Nightmare's side as she calmed a shaking hoof. Celestia was silent as she snaked her wings around the black alicorn.
"I'm so.... I'm so sorry," She sobbed "I'm a terrible pony!"
"You are a leader!" Nightmare snapped "Do not wallow in self pity for every mistake. Correct them. Admit that you are wrong! No one in perfect!"
Celestia blinked like a foal sniffling "I- Yes..."
"Apologize to everyone that you have wronged but don't leave it at that. Make it up to them, Celestial."
Celestia blushed "It has been a while since I have been called by that name."
"Celestial?" Chrysalis questioned.
"My true name is Celestial Body. I was meant to raise both the sun and the moon by myself," She blinked looking at the changeling "I apologize sincerely from the bottom of my heart for the death of your daughter and my actions."
Chrysalis turned away hissing under her breath "I am not sorry for taking over your kingdom but I apologize for putting you on the spot. It was something that should've been brought up in private."
Nightmare sent Chrysalis a small smile. Celestia rose and stepped out of Nightmare's wings.
"I will think of a good team to go to Tartarus. It would be good to sleep on." Celestia yawns slightly as she turns away with flushed cheeks from crying.
"Let us take our leave as well, Nightmare." Chrysalis stated following Celestia as a guard walked beside them.