Old scrolls of Equestria report of a once idyllic and peaceful little village inside of the cursed forest of Everfree,
which was confirmed to be the origin of one of the greatest diseases in Pony history. The princesses' researchers, aswell as the head mage of the crown, Starswirl the bearded, called this by then new found Virus the 'Mark-disease'.

The Everfree forest, a forest cursed by ancient creatures long before ponies walked the lands, has always been a mystery to researchers, mages and philosophic ponies alike. Up to this day barely anything is known about its origin or purpose. Unexplored and untouched by any hoof it still resides near the borders of a village called Ponyville. The only things ponies know for sure, is that deep within its twists and turns hide terrible creatures of immense power. Chimeras, dragons, Changelings or worse. But one does not have to be huge or magical in order to be dangerous... or deadly.

'The Mark-Disease' or 'Cutie-Mark-Disease', broke out about a little more than 1000 years ago, claiming lives in the thousands, if not even more over the course of many years. This disease, caused by a microscopical Virus found in various vegetables in Equestria, lead to a mortality rate of nearly 90% without the right treatment. The treatment itself, a mixture consisting of various rare ingredients from all over the world, was the only thing that stopped the virus from spreading. Because of its rarity and its high value, only a few big cities were able to receive it for a high price. After the new millenium has started and the virus stopped spreading, the medicine began to spread further through the lands and the disease itself was extinct... or at least thats what the ponies thought.

After the virus was pushed back, researchers of Canterlot castle were send out to search for the origin of this plague. It took them many years, but in the end they have stumbled upon its source: the dreaded Everfree Forest. This virus, found only in these specific plants and vegetables found growing in said forest, spread through the bodies of their victims, slowly destroying their white blood cells aswell as their brain cells, causing not only an outbreak of madness, but in later stages even complete loss of sanity. They became immune to pain and it took a long painful time until the victim was finally released from it by internal break down of its organs. For those who didn’t know about its existence, the disease was just looking like an ordinary 'cutie mark', visible to every pony yet hiding a cruel secret. After it came to the public, mass hysteria and paranoia took hold of ponykind.

Although there was no immediate danger of contagiousness from one creature to another, not through water or air, the virus had no problems to spread through most parts of Equestria. The only thing, other than direct consumption of the spoiled vegetable, was a bite of another infected pony. The virus itself could not survive without its protecting host and died after a short time when extracted from the vegetable.

After the virus was banned and the source of it was discovered, guards of Canterlot slowly began to lock down any entrance to the forest with magic barriers, hoping this would have been the last horrible thing that cursed forest would throw at them, but the protection should not last. After the banishment of princess Luna, the order of the regime in Canterlot was shattered and the barrier was opened to conserve magic and resources to the rest of the kingdom.
After years of peace and knowing the virus was beaten, the ponies began to live their normal lives and the researches started to forget about the Mark Disease. Some of them still argued about possible ponies who would still live inside the forest might be exposed to the same threat, but their worries got pushed back with the simple argument that 'nopony would ever be able to live in a forest such as that.'

Because of that theory, no pony was searching for possible late victims inside of the forest, or even traces of their existence. Yet one question remained: 'Who grew the vegetables and send them into the world?'

About roughly 1000 years later, royal guards investigated the sight of a specific incident reported by a young filly living in Ponyville. According to her there was a hidden village somewhere inside that forest, filled with a horrible tragedy and walking corpses. The investigations lead to the discovery of the ruins of said old village. However, there were no signs of fights, no traces of dried blood or even bodies far and wide around the village. The bodies of a few specific ponies told by the yellow filly were also never found, including the burned remains of a young pony. The guards stopped the search for clues and bodies not long after arriving and the whole affair was flagged as 'A wild imagination of a young filly'.

However... the village was never marked on any map known to the guards and if it would not have been for a strange unexplained circumstance, this village might have never been found in the first place.
What happened in that village? Was it really just imagination? And why was no pony aware of its existence?
No pony would ever know about this disease, its history or even the name of the town itself. Long forgotten in the ancient history books of Equestria.

“Zecora? Are you there?”

“Wha-? Oh it's you Twilight Sparkle, what a surprise~ I didn’t expected your visit twice.”

“Uhm, yes well... you know I just brought you some things a few weeks ago?”

“Aah, yes I remember those things indeed! It was quiet helpful and more that I'd need.”

“I’m glad I could help you with your... uhm, what did you need those things for anyways if I may ask?”

“Twilight, Twilight... magic is mysterious and hard to explain, but if you wait, learn and understand, there will be no more complain.”

“Well, that’s right, I guess... I was just wondering you know...”

“Hm? What's wrong Twilight? You're looking so deep, is there something taking your sleep?”

“Actually yes, it's about Apple bloom. She's... well, she became really anxious and timid. I don’t know, she just seems to be changed out. I just hope she's not traumatized or something like that because of our last visit in this forest. I could never forgive myself if that would be the case!”

“... don’t worry, maybe she is just scared of the forest at night. Give her some time and she will be quiet alright.”

“I... hope you are right Zecora. I just hope Applejack won't hate me...”

“Trust me, Apple bloom is very brave and strong! There is no fear in the world that will last that long.”

“Well, If you say so Zecora... okay. Although, I will still watch her for a while to see where this goes. Just in case.”

“Keeping an eye on her wont be bad I admit... but Twilight, for now just stay near her as a friend and she'll get the grip.”

“I will, thank you Zecora! Well, it's getting dark again and I would like to leave before the same crazy things happen like last time. Those stupid Tree trunks... ugh. See you later Zecora!”

“See you later my friend~ ... escape from the night... sometimes it needs a miracle, to find back to the light."

Throughout Equestria, relics of the past lay forgotten and alone.
Never truly resting... awaiting recognition.