Tanket War

Also, since when do tanks strafe?

On lvl 3 bullets come out of nowhere and kill you. Invisible enemies? Hmmm.

awesome game. i think the game would be more fun if you could combine upgrades instead of having them replace each other

The current background just doesn't make sense with trees that you can go through, I'd suggest a retro background to match the game play effects and music. The screen off set: When I played there was black space under the background above it and to the right, All the statistics as well as your logo and the menu where oriented x/y to the current existing background, but the game space was expanded beyond that. The enemies where spawning there and I could drive there, It makes the game look incomplete along with the background that seems to have no purpose. When you fix those two things The game will feel complete even with the glitches, then you can fix it up with updates to fix those glitches and to maybe make it longer, When you get the game to that completion point I'd be happy to help Identify changes that could be made to make it better. PM me when you've made some changes.

You've got some things that work here, I think you could make this work with a few adjustments.
The bad guys are pretty neat and varied. But first off I'd suggest a background change And to fix the game to fit in the screen bounds.