there is no reason to combo in this game, one of the ground units is way too strong, and all of the flying foes are way too weak.
3.5/5 overall still needs a little fin tuning
Strategy for level 4.
Get four star rocket men and just bum rush the towers. get about 18 guys to deal with the towers. KEEP building guys. use the 18 to kill all the towers and then take all of the guys you have been building during the game and create a meat wall around the hostage. this should stop the many WTF choppers that will appear at the end of the level.
p.s. Don't stop building guys even after the wall is up. Just in case.
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