Press Z to change the background. If you are using Mega Man Mode, press space to shoot. (Though all it does is show the laser blaster. No bullet comes out at all.)
I showed this to @kaie123 at ToyToy Games, and he gave him some gloves and shoes, so he now has a new design. BTW, I forgot to say that the Mega Man Mode is just testing out a way to use the separate sprite trick.