The reason it looks photoshopped to me is that the rock is far too bright for the time of day indicated by the sunset-clouds above. Idunno, maybe Blitzo just has one big mother of a flash on his camera. But the contrast between the edge of the rock and the sky doesn't look natural, nor does the angle of the clouds compared to the angle of the rock. It just doesn't jive. Then again, Blitzo isn't one to post cheap PS shots on this site, so maybe its real and it just looks uncanny. Blitzo? What say you?
The easy way to Photoshop it would be to remove the original sky and replace with the sunset from another photo. I agree, the lighting does seem unnatural. It's a low-light photo, though, hard to say if it is a merged shot or not.
it could be photoshopped it could be real. It's unfortunate that it's a debate but it is, but that being said you aren't the photographers and shouldn't say it is anything other than good or not and then ask anything else. I've taken a lot of photos in my day and in an instance like this what people aren't taking into account is the amount of cloud cover as the sun is setting there could've been a relatively small whole that the sun is able to punch through lighting the wall and creating the effect you see a lit area but a lot of dark and contrast in the clouds.