Based upon urban legends.

Part 1

A mare and two stallions from another village visited Ponyville one autumn day. They asked several citizens about a sanatorium in Everfree Forest.

"So you are in search for the paranormal? I own a book about that place!" Twilight said.

"Don't go in there! I will be too scared to visit it!" Applejack said.

"Nopony dares to go there!" Fluttershy said.

"Interesting! But be careful!" Rarity said.

"I heard about it so stay careful not to get lost!" Pinkie Pie said.

The the three equipped ponies went into Everfree Forest that sunny autumn day with a tent.

"So I heard that sick fillies where send there to die!" the stallion said.

"And there was a murder there too!" the mare said.

Evening came and the three ponies went into the abandoned sanatorium. Nopony had been there for a decade but the ponies felt they was not alone.

The ponies passed by the rooms where there was schock therapy.

"Did you hear that? Somepony is behind us!" the mare said.

Then the ponies heard crying, screaming and laughing of fillies but none was in sight.

"Hello? Anypony?" the mare shouted but nopony shouted.

Suddenly the ghost of a sick filly showed up and it chased the ponies.

"Everypony run!" the mare shouted.

The ponies ran all they could deep into the forest as the pony ghost vanished. But now the ponies was lost somewhere in Everfree Forest.

"We have no choice but to sleep here tonight and we cant find the tent!" the mare said.

Then the ponies went to sleep in the forest as nopony disturbed them. The three ponies got up in the morning and they could not figure out where they were.

"What the hay! I think we got too deep into Everfree Forest!" the mare said as she cried.

The ponies wandered on until they found some strange ponies made out of sticks.

"For Pete's sake! Even Trixie would not make these things!" the stallion said.

"Hey? Did anypony hear those screams?" the mare said as it was a scream of another creature that sunny day.

Then the voices of ghost fillies filled the forest that was too quiet, and the three ponies tried to find a way out but no luck. The ponies felt like an entity ran after them, but they did know what it was. After the ponies had followed a stream in the forest was they taking a break at last.

"Our equipment caught some activity, and it was not like anything ever heard before!" the mare said.

"I just want to get out now!" the stallion shouted.

"Calm down! I just hope we will get out of here before the sun sets! the other stallion said.