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Strange events were happening in different big cities of Equestria. An unknown creature, who was titled as Mr. X, was doing many "strange" crimes. The creature was abusing their victims for their fetishes. Mostly for various unique tickles. No clues, completely different bystanders' testimonies. It could be identified that it was a unicorn, who was really skilled in magic and hiding. There was only one distinctive feature - concealed garment as a coat, hat and a thin fabric mask on the face. To become their victim, it was enough to be rude or somehow tease them directly or accidentally. If the victim happened to stay alone afterward, then Mr. X would attack by tying and tickling them by sophisticated methods, until the victim would pass out. They didn't remember half of the happened events afterward. Maybe it was the effect of spells, or just a big stress... Any attempts to find and catch the mystery pony were a failure. Even undercover police members couldn't find and provoke them.
In one moment, they lied low for a long time, before a message about constantly laughing pony and changeling appeared. It seems like there was no reason. They both wore jackboots on their hind hooves and tried to take them off diligently and obsessively, but to no avail. They were delivered to a hospital to calm them down and sort out the happened. Doctors also couldn't get rid of the jackboots. Even invited magicians appeared powerless. They could find out that it was special portal hoofwear, the portals could be deactivated with their both sides being nearby. Some applied medicine gave some success in interrogation of Liz and Card: from the scant information, it turned out that they had become victims of Mr X. Moreover, almost simultaneously and in different parts of the city. Unfortunately, it was not possible to obtain more useful information: laughter sometimes made their speech unintelligible, as if the kidnapper knew that they were being interrogated.
The police had to use the great part of their department to find the mysterious pony. The changeling and the pony were temporarily locked in straitjackets and placed in a room with soft walls under the supervision of doctors so that they did not accidentally harm themselves. Mass viewing of surveillance cameras showed that the person had appeared at the international airport. The search and interrogation made them understand that they were a day late: Mr. X was able to bribe some of a staff on that shift. The largest bribe was received by a baggage checker, who saw strange suitcases with hind hooves, but did not report them when he was paid. The interrogation of the guard continued, while Mr. X was already too far away on the longest flight to the far-away jungle, where the chance of finding them was illusory.
Who knows what prompted them to do such a thing? Were the changeling and the pony too rough or too teasy with him? Will Mr. X return their hooves back to them? The poor hooves owners were tickled almost constantly by the most diverse and increasingly intense methods of tickling. Will they stop at the last couple of victims? One can only hope... But the sudden disappearance of one of the main detectives on the Mr. X case greatly frightened those who were also working on this mystery...