It's beatable. Just focus on getting as big an advantage as possible before dark shows up, then once it does focus 100% on keeping it from having reproduction planets. It will kill the other colors for you in the meantime, you can ignore them completely from this point on.
If anyone in Chrome is having the problem of only having a black screen, or having their flash player crash, try this: http://techlogon.com/2011/08/11/shockwave-flash-crashes-in-google-chrome/
Worked for me
As a warning, if you see a user named Dkpure in your game, leave before it starts. All he does is spam attack a country to make the timer go up indefinitely, and waits for everyone to quit. I'm sure there are others, and it's possible to make another account, but one has to start somewhere... :P
Once you get the Laser Cannon and Overkill, it gets pointless fast... with 100K exp every level you just increase max base HP by 12500... the zombies never kill it. Or you, because at this point your health is five digits. When do I stop?
Overall, the game was pretty easy playwise. However, it was very tedious, as the bubble point accumulate much more quickly than gun points, making each successive level take longer and longer to complete, as enemies have more hp and your guns' power increases very slowly. Oh, and Leech Cannon = Win.
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