The absolute phenomenon of Slenderman has appeared suddenly with a burst of static on the Xbox One and PS4 today with Slender: The Arrival, and at a low price of $7 during launch week, going back up to the standard $10 afterwards.
If you haven't played any of the Slender games, this is probably the one to start with. It has an actual narrative and functions as a sort of "greatest hits" of the series and the vast amounts of lore found in the various creepypastas.
Even if you haven't played it, I'm sure you've at least heard about it; Slender is in some way partially responsible for the total upheaval of YouTube over the last few years, with PewDiePie and others of the like gaining popularity from it. As simple as it is, it has become pretty significant, and for $7 it's worth checking out.