I think you should get rid of the p hot key for a pause menu and make upgrades p.
What's the point of a pause screen when the upgrade screen does the same thing?
And when you pause, there is no one second delay before starting the game like there is when you use the upgrade screen.
for everyone who is wondering what linox said, "As others have said, with a few minor changes, this could easily make a great multiplayer game. Add in a timer, tighter turns, and it would work almost flawlessly. A range to see how much of an arc your guns have to fire in is something that would help. Options to buy different styles of planes would be a nice reward for completing levels with full stars, and possibly stronger guns for the later levels. The base behind this game is very original, as is the gameplay. Overall, this is a very good game. As such, I'll give it a 4/5. Great work. "
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