Seeing him walk around like Doc Ock got me to thinking that Slender Man would make a good supervillain. I mean it practically writes itself.
"Joe Slim was a government agent who got caught up in a horrific lab explosion that not only gave him the ability to stretch his limbs, but gave him an appetite for his own species. Some high tech equipment was also caught in the explosion, which resulted in a time portal that sucked Slim back to 15th century Germany. He has lived on for centuries feasting on the flesh of children which he deems unsuitable for future society, and he has since adopted the name of Slender Man. And now he makes his way to to find some more victims, but will instead find himself face to face with <insert name of super-hero>!!"
Just be sure to send me a check, Marvel or DC. (I have too much time on my hands)