Perhaps you could be more specific about what you need critique on.
It is an interesting, but strange piece. If it was a character study in a series of turnaround drawings it would make more sense, but on it's own my first thought was that I had nothing to focus on. Especially with his head turned away, there is no focal point.
I agree with the above poster. Sorry I can't really crit on much, but first thing that hit me was the mountain face thing he's climbing makes him seem as if he's a few hundred feet tall. The way the cliff is done with details and such gives me the impression that a human would be around the size of his finger or toe. Not sure if that was your intention.
Also like the other poster said, there's not a great focal point because his head is turned. Maybe a better pose would have been to still have him climbing, but his head, and torso be turning towards the viewer, as if he'd ready to jump off the side towards the viewer (hope that made sense)
His right hand is holding a joystick that is so close to the head it is forming like a little unit that attracts the eye too much. Too much tension there. Also the clouds are doing the same thing, they're too interesting.
At least Icarus tried!
My Process: Dead Rider Graphic Novel (Dark Horse Comics) plus oil paintings, pencils and other goodies:
My "Smilechild" Music. Plus a medley of Commercial Music Cues and a Folksy Jingle!: