The graphics are AMAZING! The atmosphere is absolutely spectacular - well done! That said, I find the controls a little unintuitive (I spent 10 minutes just figuring out that you have to press A to select in the menu). The shooting mechanics could also be revisited differently. Also, the O2 time seems too limited (or boubles sources are too rare). Don't get me wrong, the game is certainly fun - I simply think it would be even better with these tweaks. Thanks for sharing your work :)