Once you have 4 Mother Teresa, get those towers (they suck but still you need them) Well...get 4 Heavy infantry and the rest gunners and be pissed off until you get to level 40...then you will realize... something....you haven't slept... and you have school tomorrow which is today in 2 hours...
If the level freezes, quit then continue or if that doesn't work, refresh then continue.
There is only one way to beat all 40 levels. Train 4 repairmens into Mother Teresa, healing over 1000 hp and put them at each side... even then you will need to put them togather to form a "holy shield" at some levels... Staring from level 1 you train your repairment by leaving one critter alive and have your repairment to repair that wall...forever...(3 hours) come back later to kill the critter and go to level 2, you will have more money from the "advance unit" do it again and again, until you have 4 repairmen then... leave like 3 critters alive and have these 4 repairmen do repair forever and ever. If you want to shut down your computer just pass a level and your "progress" will be saved.
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