I've taught a third grader how to do my style of art :P. Truely PS isn't that hard to use it's just coming up with the idea you want. That's where age comes it. 3rd graders don't thick that dynamic so it's hard to tell them to. But I got lucky with mine lol he's not a normal kid .

Anyway the pic looks cool, yeah doesn't seem hard but they're are fun to do. I basically like to do photomanipulations to the stock photo and set up a scene that has characteristics to the sprites.

Though you should show the stock photo to show what you've done.