Queen Chrysalis' throne has been taken by Thorax, newly dubbed King of the changelings, and Thorax's first act as king was to ally the Changeling kingdom with Equestria to prevent major catastrophes. The first few weeks reformed for the changelings were a bit sketchy, seeing as a few changelings, three to be exact, were sent over to a science facility.
"I'm not sure about this" one of the changelings said "If we're at peace with the ponies, why are we going over to these science facilities?". The doors opened the science facility, which also acted as a hospital, newly opened and ran by Princess Twilight Sparkle. The changelings walked inside, nervous about the visit.
"Ah, good to see you." Called a voice from the hallway, revealed to be a graying-brown griffon "I'm Dr. Granite Hardrock. Welcome to our science facility." The good doctor said as he was seemingly friendly with the changelings. Granite's cheery personality and friendly behavior made the changelings uncomfortable.
"Is this gonna take long?" a blue changeling asked, speaking the mind of his changeling friends.
"I'm afraid it might, but it's not like I'm gonna hook you up to any machinery that's gonna kill you or anything." Dr. Granite clarified to the changelings. "Before we begin, I'm afraid I haven't gotten your names." Dr. Garnet continued, hoping to be more friendly with his patients.
"I'm Wingspan, this is my sister Tree Sap, and the blue one is Stinger." one of them answered. Dr. Granite welcomed the three once more and led them down to the room where they'll be operating.
As they walked into the small room, they found a couple chairs, which Tree Sap and Stinger sat down in. Wingspan found an operating chair, and he thought he might as well go first.
"Ah, our first changelings here and we already have volunteers. Delightful." Dr. Granite said. Granite settled Wingspan down, and performed a quick checkup before they began the procedures. Once the checkup was complete, Granite went over to his desk, typed down what he learned from Wingspan's body onto a document, and opened up his cupboard to reveal a needle.
"Now I'm gonna need a blood sample." Dr. Granite said, holding out the needle. The needle must not have looked big to Dr. Granite, but Stinger saw the thing as huge and it scared him. The blue changeling cringed and even tried slowly to walk out of the office.
"Stinger, there's no escaping this." Tree Sap said in an emotionless tone. She did not care much for the needle as much as Stinger was, and neither was Wingspan. Dr. Granite injected the needle in Wingspan's front right leg, and out came a liquid that oozed a bright green and dark blue color, and even glowed a bit.
"All right. That'll be it for you. Who's next?" Dr. Granite asked. Stinger was hiding behind Tree Sap, who just sighed. "Let's just get this over with." She said.
The next few minutes, Tree Sap and Stinger got their checkups and blood samples taken. Dr. Granite, congratulating the three for being the first patients in this new science facility, gave each changeling a lollipop and led them back to the entrance. It was time for the three to go home to the hive.
"If you guys need anything from me, or if I need to schedule an appointment with you, Just call me or I'll give you a call." Dr. Granite assured the three, as a chariot with King Thorax in it appeared to give his subjects a ride home. As the changelings left, the griffon doctor examined what he had collected from the three of them. He had gathered samples of not just their blood, but also of their fluids, which they use to make the cocoons. For hours on end, Dr. Granite and other doctors examined the samples some more and more until it was time for the facility to close down for the night. All would go home by the time of closing, except for Dr. Granite and a pegasus janitor.
"Doctor, what are you doing?" The janitor asked. Dr. Granite was spotted taking a blood sample of his own out and putting it next to the blood samples and the cocoon fluid samples.
"I'm trying to see if I can give other species the ability to create cocoons." Granite explained, mixing the blue-green changeling blood with the red blood from his own body. Once the mixture was complete, the janitor couldn't wait any longer.
"I'm gonna give it a go." The dimwitted janitor said, as he took the mixture and chugged the small flask down faster than a jug of apple cider. Dr. Granite tried to stop him, but it was too late. The mixture was in his body and it was taking immediate effect.
"Oh no." Dr. Granite said, as he ran for help from the other scientists. The body appeared to be dead, but the coat took an immediate color change, changing from the janitors normal color, to a darker grey, and the eyes shot out glowing green and lifeless, and the mouth became expressionless, oozing out green fluids. He became infected with the DNA mixture and became a monster.
The next morning, the other scientists showed up, all except for Dr. Granite, who stayed home in horror of being fired for becoming a mad scientist and being fired, or worse. The janitor, who was stuck lying down all night, eyes open, got the attention of the other scientists.
"What happened here?" each one of the scientists asked one another. When there was a crowd of ponies surrounding the janitor's cold resting body, the monster sprang to life and bit the neck of one of the scientists. The ooze from his mouth drained and mixed with the gushing blood of the bitten scientists neck infecting them too. One by one, the process was repeated until the entire science facility was completely zombified.
And now the zombies are hungry, and it's all thanks to the changelings.
"Breaking news!" Every TV blared in Ponyville, maybe even Equestria even "After an accident at the newly built science facility, all citizens are to remain indoors unless by a Royal Guard until further notice! REMAIN CALM!". Rainbow Dash was bummed when she heard that because now she was stuck in Sugarcube Corner with Pinkie Pie for the moment. Pinkie Pie just laughed her troubles away like she always did.
"Oh come on Dashie. What could go wrong?" Pinkie Pie assured her old friend. Rainbow Dash just calmed down, but was still upset that she was told not to leave the building. The pegasus just looked outside to see what the big deal was. She saw that nobody was in the streets. Funny enough because she could actually hear something coming from outside. Something sounding like hoof steps and moaning from outside.
"Pinkie, is this another prank?" Rainbow Dash asked, concerned about what's going on.
"Rainbow, I told you once, and I'll tell you again. CALM DOWN!!! This isn't '28 pranks later' you know!" Pinkie Pie said, yelling at Rainbow Dash, confused by the reference Pinkie made. The moaning and hoof steps came closer and closer. Soon enough, the sound would worry even Pinkie. Rainbow Dash went out to the back door, peered out the window, and at first saw nothing. Then it struck. A dark grey, scarred hoof smashed through the window, clawing its way to Rainbow Dash's face, which was just out of reach. Rainbow peered through the smashed window and saw the hoof was belonging to a body that appeared dead, but walked as if it was still alive. It's glowing dead eyes peered back into the violet eyes and saw Rainbow Dash as a delicious meal for the ghoul to devour. Rainbow Dash let out a small gasp and hid in another room.
"Please tell me we have weapons." Rainbow Dash asked, panting. Pinkie wondered why she would have any, and Pinkie peered back and saw the undead corpse punch through the back door more and more times. Pinkie's eyes shot out of her head as she let out a small, frightened screech. The two ponies held each other, shivering, scared, and hopeless. The zombie broke down the door and shambled on over to Rainbow Dash and Pinkie Pie, followed by other zombies waiting to eat.
"Screw it!" Pinkie Pie yelled as she and Rainbow ran on over to the front door. The lead zombie sprayed a green toxic goo at Rainbow Dash. The goo burned her skin as if it was lava, or maybe it made Lava feel cool in comparison to the goop. Rainbow Dash screeched in pain as the goo drowned her in agony.
"Dash!!!" Pinkie yelled as she finally got the door opened "I'm not gonna leave you to die!". Pinkie tried to drag Rainbow's body out the door. The lead zombie bit Rainbow Dash on the leg, spewing blood all over the walls and the floors. Rainbows screams echoed all across town. There's no denying she was infected.
"You already did." Rainbow said, calmly accepting her fate. The green ooze leaked and fused with her blood. There was no point in fighting the infection within her body. With that moment, Rainbow Dash closed her eyes, and breathed a final sigh. Pinkie Pie ran, and the last she saw of Rainbow was her body shooting back up, with a darker grey shade of blue and glowing green eyes.
Pinkie Pie cried as she ran from the carnage she just witnessed. One of the other zombies caught up to Pinkie Pie, and was ready to spread the same ooze on Pinkie before biting her and submitting her to the infection. Before Pinkie could even recognize who it was that was that was infecting her, a silver bolt shot out of nowhere, covering Pinkie and the zombie's dead body with the maroon blood of the zombie's original body.
"Y'all right sugarcube?" A familiar voice called out. It was Applejack, who managed to build herself a crossbow. Pinkie smiled, tears trickling down her face, as she jumped up and hugged her friend. Applejack hugged back, tears falling from her eyes as well. Pinkie stopped hugging her and brushed the blood off of her already stained coat and hat. The zombies walked slowly to Applejack and Pinkie Pie, reminding them of their situation. The two ran for an old abandoned safe-house Applejack made in haste of this apocalypse.
"Was anyone with you when you were attacked?" Applejack asked Pinkie Pie, reloading her crossbow. Pinkie can't stand and have flashbacks of the attack.
"Well, there was Rainbow Dash, but she...died...trying to escape from me." Pinkie said. Once again, tears down her eyes. Applejack almost shed another tear, recollecting all the good times Rainbow Dash had with her in life.
"Well, at least there's 7 of us now. There's me, you, Twilight, Fluttershy, Spike, Starlight, and--" Pinkie said, trying to cheer the two of them up, but was interrupted by Applejack, who started crying quietly. Something happened and Pinkie just knows it.
"Is there...someone who's not with us?" Pinkie Pie asked, cautiously. Judging by the look on Applejack's face, she suffered a fate similar to Pinkie Pie's.
"I was at the Carousel Boutique with Rarity when we were attacked. They came in through the windows and burned us with a weird goop. Rarity...didn't make it." Applejack said with each sniffle and tear as she pulled out a necklace Rarity gave her earlier. "This is all I...all WE have left of her". And with that, the cowgirl burst into tears once more, unsure of a plan.
"Well, we can't just sit here. We have to make a stand. We have to fight. We have to--" Pinkie Pie proclaimed at a small grey-purple hand extended, exposing the base. They recognized the body as someone they knew, but they were afraid that whoever it was, not only became infected, but exposed their hiding spot. Spike was zombified as well, followed by the zombified corpses of Rainbow Dash, Rarity, and almost 25% of Ponyville.
"RUN!!!" Pinkie Pie said, yelling to finish her sentence. On the run, Applejack found a broken splinter in the walls of the hallway. Applejack ripped out the plank of a splinter and gave it to Pinkie Pie as a weapon for her to use. The zombies trudged across, closer and closer to Applejack and Pinkie Pie. Applejack fired her crossbow, causing an explosion in one of the zombie skulls, causing a bloody explosion. Shortly after, another one of the zombies sprayed its mysterious goop once more, and the goop landed on Pinkie Pie, burning her as if her skin were falling off. Pinkie Pie screamed in agony, and fell onto the floor.
"I'm not giving up on you Pinkie!" Applejack said as she picked her up and ran father away until they spotted an old elevator. Applejack put Pinkie's injured body on the ground and pulled the rusty lever. The doors to the elevator shut before the zombies could get to them, and hoisted Applejack and Pinkie Pie up until they reached the top floor. They found the elevator lead to a mining cave nearby to Everfree Forest, which meant one thing for the survivors: Fluttershy's nearby.