Slenderman

Slenderman is, as his name suggests, a man who's primary describable feature is that he is slender. He also bears a resemblance to Lord Voldy-Mort, and the general creepiness and not-wanted-ness leads many to believe they are somehow related.

Slenderman prowls forests on Earth, snatching children for reasons unknown. He appears in many forms, the most common of which is a faceless, suited tall man who just seems to... appear....

He was first sighted in 2009 PLF when people began to notice a strange faceless man in random pictures taken in different eras. At the same time stories began to crop up of a faceless man attacking people in a forest. A farmer claimed to have shot the arm off of Slenderman, only to find a sleeve in the ditch which disintergrated on sight.

Not only that, but children began to go missing. Several sightings report a multi-armed, spiderlike entity with malevolent intent attacking them in the forest, and League officials initially thought that the entity was another survivor of the extinction of the Money Spiders. Recent sightings have conformed, however, that this thing is another entity entirely.

One of the theories regarding Slenderman's sudden appearance is the Tulpa effect, by which if enough people believe in something it spontaneously becomes real. Another theory is that Slenderman mutated from another entitiy known as a Shroud, since these are actually fairly common throughout the Galaxy. This theory has been disproved, however, by Shroud experts Galaxy-wide.

The Mystery of Slenderman remains a mystery, and its secrets may never be revealed. Slenderman sightings stopped dead after 2011 PLF and there has been no record of any of his appearances since. What a pity.