You have some performance issues. Consider adding a method that deletes the lasers once they leave the screen area. As it is, the longer you play, the slower it becomes. Also, an alternative choice is to draw a line using a greenfoot image. This way, you would check for anything in the line. It would look much more 'Death-Laser' -ish, plus it would run like a breeze.

If you want some critiques here they are: 1. Gameover screen is a bit disappointing, you could try looking at some other professional games for good ones. 2. you could allow the person to turn when still, but add a penalty to it, AKA make it slower. All in all, you are doing an awesome job! :) (In order to make the player move, you could have a chance for a red tank or something to spawn, which the red tank could shoot back at you. This way, its not a 'bullet-hell', but it still gets the person to move. As it is, you can essentially stay still as long as you don't care about gaining back life from the crates.)

NICE!!! Also, you don't have to make a new project, you can just update the old one. Other recommendations: enemies shoot (only if you want it to be a type of "bullet-hell"), and possibly making it take longer between shots. Other than that, phenomenal!

Nice! I would suggest you reduce the turn speed of the player tank significantly, and possibly make a turret on the player, that way it looks more like an actual tank. Also, if you can, try using GIMP or another paint software to make a better background. The current background looks a bit tacky. All in all, a really nice game.

Great. One problem is that the speed bar messes it up*, and so does remedially spamming the space bar**. *Audio becomes disconnected from video and video occasionally stops altogether **Will not resume when you press spacebar.