A very nice game!
I think this game is just the bee's knees. I've shown it to 5 or 6 of my friends and they simply love it.
What I love most about this is the character design. Chiseler looks like he could be a Nintendo character, and all the graphics and musical elements fit tightly together.
I think you can even improve upon this even more if you add a shop or levels in which you can get certain powerups and armor. It would be nice to have score saved progressively through levels to use as currency for said shop.
Overall, a very nice game and I find myself coming back to play through it often!