"Now, a rainbow's tale isn't quite as nice
As the story we knew of sugar and spice,
But a rainbow's easy once you get to know it,
With the help of the magic of the Pegasus Device..."
--WoodenToaster, Rainbow Factory
Everypony in Equestria knew of the pegasus wonder known as Rainbow Dash--the only pegasus able to pull off the legendary Sonic Rainboom not just once, but twice; winner of the Best Young Flyer competition; Wonderbolt-in-training; Element of Loyalty. It seemed like there was no obstacle this pony couldn't tackle. Nopony would have guessed that her fall from grace would come from within her own mind, in the form of one of her best friends...
"Let's delve deeper into rainbow philosophy,
Far beyond that of Cloudsdale's mythology.
It's easy to misjudge that floating city,
With it's luring decor, and social psychology..."
Rocket to Insanity
After her second year in the Wonderbolt Academy, Dash was being plagued by horrid and recurring nightmares that would leave her waking up screaming and unable to get any sleep at night. The dreams were always about her friend Pinkie Pie brutally torturing and mutilating her, then baking her into cupcakes or some other party favor for her friends to feast on. These dreams were so vivid and so real, they were beginning to take a heavy toll on her daily life, often forcing her to sleep during the day and interfering with her work and time with her friends. Pinkie Pie took notice of Rainbow's change in attitude and invited her to Sugarcube Corner to give her something to cheer her up--a nice fresh batch of cupcakes! At the very sight of that tray of cupcakes, all of those months of horrific visions and nightmares came flooding back to Dash's mind as she was faced with the fear that her dreams were about to actually happen! As she backed away and pleaded with Pinkie to stay back, one single thought crossed through her mind...
"Kill her... or you will die..."
Without warning, Dash grabbed a nearby knife from the counter and began brutally slashing and stabbing at Pinkie Pie, the pink mare's blood coating the floor of the kitchen as the life faded from her body, her eternal party finally over...
Dash was left to look upon what she had done, and let out a scream of anguish as she cradled Pinkie's body... She had committed murder... Nopony had committed murder in over a hundred years... As she felt the blood soak all over her body, she began to do what Pinkie taught her to do... Giggle at the ghastly... Snortle at the spooky...
Dash fled Sugarcube Corner just before Pinkie's body was found by Mr. and Mrs. Cake...
"But with all great things comes a great responsibility,
That of Cloudsdale's being weather stability.
How, you ask, are they up to the task?
To which the answer is in a simple facility..."
The Proposal
Despite having killed her best friend, Dash was grateful that she was sleeping comfortably for the first night in a long while, the nightmares having seemingly faded. However, the night after Pinkie's funeral, she was awakened by the feeling that there was somepony in her room... Indeed, when she opened her eyes, there was a red pegasus stallion with a white mane and tail standing at the foot of her bed!
"You sleep rather soundly for a murderer... That's good... You'll need a clear conscience for what I'm about to propose..."
The pony introduced himself as Dr. Atmosphere, an employee of the upper Rainbow Factory in Cloudsdale. Dash knew of the reputation of the factory and the rumors that spawned about what went on there, being that it was restricted to all personnel from the lower factory... Dr. Atmosphere explained to her that every horrible rumor she had heard was true... Yes, fillies that failed their exams were sent to the upper factory, and yes, they were ground up into the colorful spectra that gets sent to the lower factory to make rainbows. He explained that he had been eyeing Dash as a potential employee of the factory for a while, ever since that second Sonic Rainboom, and now that she was on the verge of possibly going to prison for life, he felt it was time to recruit her as the factory's new supervisor, as the old one couldn't take it anymore and had killed himself by throwing himself into the spectra-making machine known as the Pegasus Device. Dr. Atmosphere also noted that Dash would be able to indulge in those psychotic urges she felt while killing Pinkie, while still being able to live her old life outside the factory, a privilege few workers got to share... He warned her, however, that if she refused, Celestia's guards were ready to take her to prison immediately... With no other options to survive, Dash accepted her new position and took up the mantle as supervisor of the upper Rainbow Factory...
In exchange for her acceptance, Dr. Atmosphere used his influence to help speed the investigation into Pinkie Pie's murder along, eventually pinning it on the innocent schoolteacher Cheerilee after it was revealed that she and Mrs. Cake had gotten into a dispute over prices the morning of Pinkie's death... It didn't take the citizens of Ponyville long to piece together what they thought happened... Cheerilee had snuck into the kitchen and killed Pinkie Pie in cold blood to get back at Mrs. Cake! The entire town was outraged, and formed a lynch mob to burn down the schoolhouse with Cheerilee inside... Her screams and cries of innocence echoed with the cheers of the crowd into the night as she slowly burned alive...
"In the Rainbow Factory,
Where your fears and horrors come true...
In the Rainbow Factory,
Where not a single soul gets through..."
Rainbow Factory
Rainbow Dash now works as the lead supervisor in the upper Rainbow Factory of Cloudsdale, spending her days with the stench of blood in her nostrils from the countless fillies and colts she's sent to the unforgiving maw of the Pegasus Device. But that's not all she's done... Since they obviously don't need all of the little ones they get to fill their spectra quota, Dash has taken the liberty of setting up a sadistic torture room to help the morale of the other workers. Most if not all of them are all secretly convicted killers and psychopaths, and would just love getting one of those tasty fillies to themselves for a while... Outside of the factory she continues to interact with her friends and train to be a Wonderbolt as if nothing is going on, always returning when she needs to unwind and use a filly or colt for a punching bag...
Oh, and mentioning the C-word in front of her will send her into a full psychotic rage, and may lead to serious injury and in most cases death... What is the C-word??? Why don't you try asking her if you're feeling brave???
UPDATES
--Found a loving wife in the form of one of her alternate selves, Rainbow_Dash2
UPDATE2
--Obtained the form of a dragoness after being unbirthed by GoddessViolet; she is now the goddess' daughter, and the abilities she inherited from her mother allow her to change her size and become a macro. She also inherited her mother's strong, musky, deadly aroma...
UPDATE3
--After a night of fun in her dragoness form, she has gained an obedient slave and fucktoy in the form of Morphinia, whom she allowed to impregnate her.