Superb work! I love that grunge effect, some people will tell you that grunge effects are the easiest thing to do, but that aint true. Your wall is the perfect exemple of that, the light and dark is very well applied, the texture is great and the character rocks! Some grunge walls are really artisticly poor because people will think alll you have to do is applied texture here and there and voila!....
5 stars material here! keep it up