Thats nice, I wouldn't mind knowing how to make a background like that, the problem is the render, Mario, does not suit the back at all...
Well I'm sure you have played some of the classic mario bros games, so one that reminds me of Mushroom Kingdom (or whatever it is called) really I don't think Abstract brushes u are using are very good for mario, when I think mario I think green rolling hills, not futuristic abstract.