I just wanted to make a note about the in game controls.

Using a Xbox360 compatible controller is the preferred way to play Nine Worlds.

DPAD - Left & Right
Button 1 - Jump
Button 2 - Attack
Button 3 - Use equipped potion

In the games menus you can use the Forward and Back buttons to for example go back or play next level respectively.

Nine Worlds is also playable without a game pad, use the keyboard to control the character.
A - Left
D - Right
N - Jump
M - Attack
B - Use equipped potion