Because pixely imp tits, that's why. :V
That's it?
For those of you who don't know but are curious, it's basically a rule34 reskin of Doom. Give it a miss unless you are into that kind of stuff or like the novelty of it.
Just noticed that I don't have any friends on steam who have one of those idiotic clan tags. Now that I mention it, I haven't seen anyone with a clan tag (that I can remember) in the last handful of years.