lenderman was added in the Slenderman expansion to the Kingdom Death: Monster core game.
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White Speakers whisper stories of the walking water. An entity capable of making people vanish without a trace, like the water of an unwatched urn. It's motives inscrutable and it's description warping with each new telling. Little is known of the Slender Man as it leaves nothingness in it's wake.
"The Slenderman is a dark, cold hole in the memories of the few that have seen it and lived. Within this chilling gap of recollection, terror thrives, growing into panic and jumbled tales of warning."
"One day, a lonely man came home and found his long, lonely hours no longer troubled him. In fact, he could not remember them at all. Each day, he left home with a chilling ache in his bones and no memory of the day before. One day, he came home to find that he was not alone, after all. Then he was gone"
The Slenderman primarily exists on a strange, watery plane of existence, referred to as the Dark Place. The creature has the ability to move back and forth between the human world and the Dark Place at will. The Slenderman is also able to imprison survivors in the Dark Place, sending them to drown via a pitch black pool of water which forms at the survivors feet.
After its initial arrival, the Slenderman latches onto a settlement and torments its populace, unseen from the shadows. Slowly driving the survivors into madness. Even survivors who have directly fought against the monster will immediately forget about its existence after the fight has ended. All that is left behind is the strange remnants of the Dark Place for the survivors to puzzle over.
The Slenderman is a nemesis monster added in the Slenderman expansion. The expansion replaces the Armored Strangers settlement event, as well as removing the King's Man nemesis from the game.