When the game is paused there should be an option to disable the mouse. Once you do that, it should use the right thumbstick to aim.
Thank you for the feedback! I'm glad you enjoyed it. The full game includes endless play as well as boss levels.
The Ludum Dare version is older, with unfixed bugs and without the proper boss at the end. If you're not playing specifically to rate the Ludum Dare version then we recommend you download the latest.
