if you missed a letter and your map shows you already searched the area, you might as well start over, I struggled to find L, I started over and found it a lot faster by using the map and not running through sections.
sneaky start: press up a split second after the "get set" first appears (literally wait a tiny bit) and you should get the sneaky start when it says "go" (if you wait til "go" to press up you won't get it, "get set" still has to be on the screen.
Best way to start is with two electro towers, one rifle tower, max the rifle tower, then upgrade 2-3 stars each electro, then built an additional rifle tower closer towards the end to catch any green troops that get past your other towers. Max all towers. Then save up for a snipe or MG tower (I prefer snipe) and max that out. Then save up and build Heat ray towers. anywhere from 4-8 fully maxed Heat ray towers will be enough to complete a level (supporting your other towers of course) Theres no reason to build any other towers other than to see what they do, and remember to go back and re-beat levels for extra skill points (use on extra damage and extra cash) if you have trouble getting past later levels
I couldnt get past level 4, so i went back and rebeat the first 3 levels and got more skill points and plowed through the game. Spend money on Grenadier and or Mercenary and you'll be fine. Pausing and letting the creeps burn, GENIUS sirbalynn GENIUS!
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