Wow, it seems like it's been awhile since I've seen a genuinely scary cartoon like this. The freakiest part was probably how it got distorted after awhile. I had seen various Slenderman games before, but I don't recall the last time there was simply a Slenderman flash. It reminds me of a Slenderman prank I saw on a video earlier. The animation was really good. It was so nice to see things get gradually creepier.
I was pretty scared when it became just darkness after awhile. I was afraid it was going to turn into one of those "screamers". I guess it would be appropriate. I like how the Slender Man sort of turns from a tree into his true self. Then again, I haven't seen that many videos with him.