Hitori Kakurenbo (ひとりかくれんぼ)

Some say it was whispered for generations in parts of Kansai and Shikoku; others claim a university club invented it deliberately to observe how urban legends spread. Whatever its origin, the night a detailed set of instructions was posted to a major message board in the spring of 2007 marked the moment this game began seeping silently into darkened rooms across Japan.

It is considered a form of spirit-summoning, much like Kokkuri-san, yet those who know it say its nature is fundamentally different — where Kokkuri-san calls something in from outside, this ritual carves the curse into the player themselves. Rice stands in for viscera, red thread for veins; a doll is sewn shut around a clipping of the player's own fingernail. In that moment, it is said, the doll ceases to be a toy.

At three in the morning, every light is extinguished save for the static haze of a television set, and the doll is submerged in a filled bathtub. The player declares three times, "You're it first, because I say so," and the game of tag begins. The doll is stabbed with a blade to pass the role of "it" back, and then there is nothing left to do but flee to a hiding place where salt water waits.

The accounts of what follows are not consistent. The television switches itself off. The sound of water moves down the hallway. The door of the closet where the player is hiding groans from the inside. Whether these things are the doll's doing, or the doing of something else the doll has drawn near, no one has ever been able to confirm.

To end the game, the player must take salt water into their mouth, find the doll, and declare "I win" three times. The window is said to be somewhere between one and two hours. The accounts of those who exceeded that limit were never finished — the posts simply stopped.

The doll must always be destroyed by fire when the game is done. Rumors of abandoned dolls — left in the backs of drawers or forgotten in closets — that left wet stains in the night still drift through the quieter corners of the internet to this day.