To load up the game right click and press play.
My advice for these 3 badges is to upgrades rate of fire then shield of main base, this should carry you through to the hard. If you are really good you should also get the 3 platinums for the impossible except the disabled one.
For the disabled plat you want to get some flak upgrades too and spam them, make sure to keep that tower alive.
A bug that would help you, especially with the impossible badge is to right click during game, this will pause the game and mean you can keep firing rockets perfectly without having to rush as you can aim (might be fixed on some web browsers or just doesn't work at all).
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