Pony Impostors

There is 1 changeling among us.

Twilight Sparkle, Applejack, Rarity, Fluttershy, Pinkie Pie and Rainbow Dash stood in the cafeteria of the Skeld One spacecraft. They all looked at each other for a moment. Each of them knew that one of them was not who they said they were. One of them was a changeling in disguise, but they would have to wait to see who the changeling was, hopefully not being killed in the process.

They eventually went their separate ways to complete tasks on the ship. Applejack went to MedBay first to sort some samples of different rock that needed to be analysed and submit her medical scan. Pinkie had to sort out a Wi-Fi issue in Navigation. Rainbow Dash was given the gruelling task of running to and from Storage to fuel the engines. Rarity decided to go to Admins first to sign herself in. Fluttershy had several tasks to complete in Electrical, including fixing some broken wires and redirecting power to Communications. Twilight had many tasks to do, but instead went to Security to watch the CCTV in real-time, hoping to catch the bug.

Rainbow Dash finished filling the engines with fuel quickly, thankfully. What was odd was that nopony had passed her whilst completing her tasks. She went to check on Twilight, who was thankfully fine.

"Hey, Twilight, did anypony trot past here?"

"No. I've seen you completing your tasks. Rarity has been in Shields and Navigation as well as Admins. Pinkie's been Pinkie, I think. She's been running around the ship quite quickly, but then she often jumps wherever she goes."

A scream echoed down the halls. Twilight and Rainbow flew there as quickly as they could. Twilight would have teleported, but the use of magic on board the ship was forbidden because it usually ended up breaking the not-quite-state-of-the-art equipment on board.

They entered MedBay, and the scene before them brought them skidding to a halt. Applejack was dead on the floor, laying in a large pool of blood and her head a little distance from the rest of her. Fluttershy, Rarity and Pinkie all stood staring at each other wordlessly. There were many rolls of bandages and surgical scalpels on the floor. Twilight demanded that everypony went to the cafeteria so they could talk about what happened.

"Right, girls, where were you all at the time of the attack?" Twilight questioned them all.

Rainbow spoke first. "I was fuelling the engines, and once I was finished I came to check on you in Security, Twilight. There's no way I could have got around the ship quick enough to attack Applejack, even with my speed. I would have had to perform a Sonic Rainboom, which would have been pretty cool up until the point that it blew apart this wreck."

"I believe you, Rainbow. The scream sounded like Rarity. Was that you?"

The unicorn's horn lit up, earning her an angry glare from the others. She levitated a travel cup of coffee over to where she was sat and sipped from it. "Yes, it was I who screamed when I walked into MedBay and saw Applejack, as I have the mundane task of starting the Reactor and was heading in that direction when I noticed the mess. I knew immediately that there was no way of saving her. I noticed that a metal box of surgical tools had been opened, and most of its contents had been spilled. I screamed, and both Pinkie Pie and Fluttershy were in the cafeteria, allowing them to get to the scene of the crime faster than you and Rainbow Dash."

"You're very observant."

"Have you looked at the amount of Shadow Spade novels I read?"

"Fair comment. How about you, Fluttershy?"

"Oh. Um. I was, er, in Electrical. I, um, fixed some wires, and sorted out the Distributor. The last pony who used it left it in a terrible mess. Then I had to direct power to Communications. I was in Storage, and went to look for Pinkie to, um, make sure she was ok I found her in the cafeteria. We both had to go to MedBay for our medical scan, and when we heard Rarity's scream we both ran there as fast as we could."

Pinkie piped up, "I know the second part is right, but I'm not sure what Fluttershy was doing before she came looking for me. I think it's a little suspicious, don't you?"

"Pinkie!" gasped Rarity. "She went to make sure that you hadn't been caught by the changeling! How could you accuse her?! In fact, I now have not a doubt in my mind that it was you."

"I think it's Pinkie," sighed Twilight. "You gave yourself up, I'm afraid."

"I agree. The real Pinks would never accuse Fluttershy of all ponies."

"What?!" asked Pinkie, bemused. "I didn't do anything! I've fixed the Wi-Fi in Navigation and sorted out the steering and everything! What are you going to do?"

"What do we do?" whispered Fluttershy.

"There's only one thing we can do," Twilight announced with grim determination. "This changeling has killed one of our friends, and should therefore pay with her own life."

Silence fell across the table. Nopony could tell what the others were thinking due to their faces being covered with visors, but the air was full of tension. A robot in a deep green spacesuit, distinguishable from the crewmates by a digital screen where the visor would be, led Pinkie to the airlock.

The four remaining had to continue repairing the ship, though they worked slowly and solemnly. None of them stayed together, wary that one of them could still be The Changeling.

Twilight was in MedBay, cleaning up the mess and submitting her scan.

Fluttershy was downloading some maps in Naviagtion.

Rainbow was in Shields, making sure the spaceship's protection had not been damaged by the changeling.

Rarity was in Security, watching the security cameras, where she witnessed Rainbow walking past Navigation towards Weapons, only she did not make it there.

She gasped, and galloped towards the cafeteria, where she would be able to call an emergency meeting to tell everypony what she had seen. However, before she was able to press The Big Red Button in the middle of the table, the wail of a siren echoed through the halls, accompanied by a robotic voice.

Oxygen depleted in thirty seconds.

She sighed, and ran in the direction of the oxygen tank in Admins. There was a sticky note with the pin code for restarting the air circulation system. Eventually, she had punched in the code and somepony did the same at the other oxygen tank in O2, with about ten seconds before the oxygen ran out.

Finally, she was able to call the emergency meeting, and she told everypony what she saw: how Rainbow Dash had headed towards Weapons and been killed on the way, but the killer had not been caught on camera. She instantly blamed Fluttershy for the crime, as she had been the closest pony at the time. Her fate was decided instantly, and she went without a word.

Rarity watched the screen of her computer fade to black, before the word Defeat appeared in red. The figure of a pony in a purple spacesuit popped onto the screen a second later, and she internally sighed. Who would have guessed that the impostor was Twilight?! As Rarity thought about it, though, she realised it would have been easy for Twilight to go around the map on a killing spree. The air ventilation system linked certain rooms, such as the MedBay and Security, so while Rainbow Dash was busy fuelling the engines, she could pop over to MedBay to finish off Applejack. Nopony watched her have her scan in MedBay after that, so she could have travelled towards O2 easily to kill Rainbow. It would have been easy to sabotage the oxygen tanks; she didn't even have to be near O2 for that to work, it happened at the press of a button on the computer.

Rarity would have to go and give that sneaky mare a talking to later, but for now, she felt it was time for another round of the murder-mystery game on these new computers from the other side of the mirror portal. She had a score to settle, after all. Framing Fluttershy and Pinkie for the crimes she committed simply would not do.

The image of the Dropship faded and the next game began.