Pretty cool. You seem to have your "style" figured out, which is a good thing. I'm not too much of a fan of the odd blurry, wavy lines coming out of the characters, but I suppose that's more of a preference issue than an issue with how it was executed. I guess that would make it hard to offer much constructive criticism since I'm somewhat biased.
I kinda wanna know what's going on in the background. Seems like they're just jumping in darkness or something. Maybe try a stylized backdrop from the mario games or something? That might look really neat.