The best trick for the boss is have maximum starting mana, lower mana cost, more mana gain per kill and everything else to basic starting gems. The first waves should be waay too easy, upgrade every time you can the mana pool (8% more mana per kill every time this is upgraded) I upgraded it until it costed something like 1300, then its just water traps and placing armor gems at the beggining. I passed it in my first try, without even letting the final boss go through once.
I recommending adding a Kill Count to the towers you build. This way you can really know if they are being helpful or not and strategics accordingly. Great game!
My best stragety was to max out mana, zombies, mana regen, and most people at once on the screen. I spawn a zombie, and 30 seconds go by, and i have 50 zombies!
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