Having gone looking for Fluttershy due to her sudden disappearance, Twilight decided to venture out to the evergreen forest to see if she could find any traces or tracks left behind by her beloved friend. Upon seeing the mutated and disease ridden pegasus Twilight was taken aback. She had to find out what happened to her beloved friend. She began to patrol and survey the area her friend resided in, wishing to find a way to remedy the disease before it got worse. By this time Fluttershy was at Stage 2 of the infection, able to move but beginning to release pollen and spores off the spotted divots on her dulling pelt. One night while investigating Twilight got a bit too close to Fluttershy, spores/pollen flying into her nose and eyes. She began to get an immediate reaction and fled the scene as soon as she realized she had been exposed. She fled to her castle.
As the disease began to take over Twilight decided to begin documenting her changes. She recorded tapes stating all her symptoms, showing examples of exposure. Due to her now sealed fate, she made an effort to gather up evidence and specimens of what led to her infection, gathering pollen, spores and flowers from the infected area and her own body. She would then lock herself in a private room to prevent herself from exposing anyone else to the disease. Before reaching Stage 2 Twilight sent out an emergency broadcast urging ponies to stay far away from the Everfree Forest. A mass hysteria would ensue.
Corrupted by their intense overwhelming desire to fulfill their destiny, the Elements of Harmony began to transform and warp as their desire began to grow into a hunger for something greater.
Unfortunately, as this began to take place Fluttershy was exposed to a vicious form of Swamp Fever. This lead to a rapid increase of symptoms, the desire and hunger speeding up the process in which she became infected with a now mutated disease- Mystic Corruption.
Mystic Corruption causes the infected victim to start transforming and begin fusing into their cutiemark. Due to this corruption the infected will begin to act out in order to make sure they fulfill a propecy created by their sudden wave of delusions. The victim will begin to enter a state of psychosis as their mind is overtaken with a insatiable hunger, a hunger they have no way of satisfying. Their mental sanity begins dwindling due to the overwhelming agony and discomfort the body is going through. The worst part to this disease is that as the pony transforms, the disease keeps the pony fully conscious. The pony is able to hear, feel and think whilst stuck in their mind. The infected will begin to act against their own will, no longer able to control their own actions.
The internal organs begin to liquify or crystalize, causing large sharp protrusions, rotting flesh, feather loss, hair loss, flexible bones and hypermobile joints. Depending on the location of where the pony desides to stay once the infection takes over it will occasionally begin to fuse with its surroundings. In Fluttershys case due to the initial cause for illness being swamp fever she has began to transform into a tree. She is unable to move effectively as her limbs begin to take root.
Fluttershy will become the main source of this now mutated disease. Any exposure to the flowers she will create as she grows into the same trees that infected her will cause immediate reactions!Starting with bloodshot eyes, bloody or runny nose, heart palpitations, vertigo and a overwhelming sense of confusion.
