An Old Whooves Tale.

A powerful ray of blue and black magic shot up out of the top of the castle and into the swirling clouds of the sky. The wind it caused was so powerful that it nearly knocked the Doctor and Derpy off their hooves. Derpy put her hoof up to shield her eyes and yelled out to the Doctor, “Doctor what’s happening?”

“The creature, its finally taken control of Princess Luna! We need to get into the TARDIS!”

Derpy and the Doctor retreated into the TARDIS and from the castle an army of Pegasi began to flood out of the top where the magic blast was coming from, like little demons covered in black and blue fur that resembled the night sky. All the ponies flew towards the cities of Equestria. In the TARDIS the Doctor was pacing around hitting himself in the head.

“STUPID STUPID STUPID. I am a bloody idiot how did I not see any of this coming!”

“Doctor it’s okay!” Derpy tried to ease him, but it did no good.

“No it’s not okay! I was a bloody idiot! Of course the dark matter creature wanted to get to Princess Luna! She’s the only being in the universe that can cause eternal night! They need night so they can survive!”

“Doctor it’s not your fault it was mine!” Derpy exclaimed. “If it wasn’t for me becoming possessed by that thing and leading her into a trap, none of this would have happened.”

“No Derpy I’m sorry that burdon is still on me. If I was smart I wouldn’t have gotten cocky back in the castle, I wouldn’t have taken you in there in the first place. Yet that one pony sacrificing itself managed to get enough dark matter particles in you to multiply and I didn’t even think to scan you before going to the castle. STUPID!” The Doctor yelled again and sat on his hind legs arms over his face. Derpy walked over and put her arms around him.

“Okay so you made a few mistakes Doctor, no ones perfect. We’ll just have to get back to Canterlot and find Princess Celestia. She’ll know what to do and how to help.” The Doctor sat there frustrated for a moment more and then took his hooves away.

“Righto, come on Ms. Hooves we have a job to fix, advante!” The Doctor called out switching a few knobs and switches.

The TARDIS faded into the balcony of the castle, and the Doctor stepped out.

“Oh my god.” He said in shock as he saw the flood of pegasi and earth ponies that were flooding their way into the nearby cities of Canterlot.

“Doctor, it’s an all out war!” Derpy cried out. The Doctor stayed focused on the flood of armies that continued to flood in, when a white alicorn caught his eye.

“Princess Celestia!” Derpy cried out. The alicorn flew and landed near the Doctor and Derpy.

“You, I’m guessing you must be the Doctor and his companion?”

“Yes ma’am that’s right,” the Doctor responded.

“Good now tell me what is happening here? Who is causing such destruction on my lands?” Princess Celestia said this with genuine panic.

“It’s the dark matter creature that I told about in my letter Princess, however- there’s more to it now.” The Doctor hesitated.

“What?” Celestia begged. However the Doctor couldn’t speak. “Oh for heavens sakes what could be worse?”

The Doctor let out a sigh and told the Princess, “The creature has taken control… of Princess Luna.” Princess Celestia stumbled back in shock and her yes went wide.

“No…no not my dear sister no! Please Doctor there has to be something we can do!”

“Yes, there is. We can protect your lands and your people with the royal guard for the moment and hold them off till we can stop the creature from controlling the ponies.”

“I meant about my sister Doctor!”

“I know your highness, but at the moment this is a more pressing matter.” Celestia opened her mouth to speak, but then closed it and turned to Derpy.

“You, pegasi; go down and tell the general to mobilize all available troops from far and wide to protect Equestria. Tell them to only disable not to kill, these are still my little ponies after all.”  Derpy nodded and flew off down stairs to find the General.

“Now Doctor, about my sister-“ however the Doctor cut her off.

“I did not want to address this in front my assistant Princess, but it must be heard now. You have to very quickly accept the fact that we might not be able to save your sister.”

“Wha- what are you talking about Doctor? Of course we can-“

“Princess please listen, this dark matter energy is very tough stuff. It took nearly everything my time machine had to extract the little bit out of my assistant. For somepony like your sister, who is the new host of the creature and in full possession there is nothing that can be done at the moment to cure her.”

“But Doctor I can try some of my magic and we can try reasoning-”

“Princess please, I do not enjoy telling you these things, but I do because they are true. The only magic powerful and pure enough to free your sister are the Elements of Harmony.”

“But Doctor I cannot use the Elements of Harmony, not without my sister.”

“I assumed so Princess, that’s why I have told you to accept your sister is gone, for now.”

“She is my sister Doctor, she is as important to this world as the sun itself, and I would never think about trying to use them on my own sister!” The Doctor realized he was never going to get anywhere with Celestia like this, so he had to focus the situation on something else.

“This creature your highness. Its weakness is sunlight; now I believe that if we can isolate the host and bring the sun up to expose the rest of the ponies. It might spare them the destruction and simply destroy the antimatter inside them.”

“Doctor hold on. Your plans are sounding paper thin, you mean you don’t know if it will work?”

“Honestly no your majesty, but it’s the only thing we can try while trying to save everypony from certain destruction. If a pony is now is exposed to sunlight then they will surely die, I have seen it myself.”

“Wait, Doctor we have to try reasoning with the creature first. Maybe the little bit of my sister that’s still in control will pull through and expel the creature.”

“Princess the beast is too strong-“ Celestia cut him off.

“You do not know how strong Luna is! You have no idea! She is as strong as I am and without her the world as well as myself are in disharmony. Now Doctor I’m going to find her and reason with her.” She said sharply. Celestia unfolded her wings and flew off to the center of the flood.

“Princess NO!” the Doctor called after her, but she was out of reach and flying tofast. Derpy came back up the stairs.

“Okay Princess I instructed the General- Princess?” Derpy asked. “Doctor what happen to the Princess?” The Doctor only stayed silent and looked toward the sky.