If their formation is 4-3-2 then use goal hang and rush their goal. You can throw it in by slipping a bit to either side, or just run it in. If you don't win by 10 or more, something is wrong =P.
I recommend adding extra missions that are replayable. They should give less money and not unlock anything, but it would give people with less skill the ability to catch up to the enemy's level as in Monster Slayers. Also, lives are unneccessary.
Strategy:
Ignore enemy attacks and spam goldmines. Keep drawing for them too. Also, grab a crystal mine to cause your crystal count to rise. Use Parting Gift (send a few units out to grab some souls). When the income is 11 or up,(preferrably 15 or so), then spam peasants like crazy. Deploying 100 peasants should be instant victory unless you moved to slow. Then parting gift might kill you before your opponent. Since the peasants will either die or go into the portal you just have to keep an eye on your own portal hp. Getting Decker, More Goldmines, and Siege Weapon is also ideal if you can spare the resources. Also try having 2 goldmines when you start. Keep reposting to keep alive or vote up!
4 endings are nice, but doesn't science ending become worthless if portal is still open? Plus, creating a government doesn't cure the zombie apocalypse.
Glitch: Purchase only the flame thrower and any perks you like. Upgrade both weapons until you can't upgrade anymore. While using the flamethrower, press e and all 30upgraded pistol bullets will mow the enemy down. Becomes even betterwith split bullet
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