Ok, so the boss is frustratingly hard, but maybe the modern gaming community are pampered in this respect. Also, well done LabuGames, this is a fun, repeatable game.
The upgrades are more useful for overcoming logistical constraints, or for strengthening your strategy in one area eg. upgrading to make the most of stun
 "Band Of Heroes"){kind=icon}
 "Giants and Dwarves TD"){kind=icon}
 "Active Defense Revolution"){kind=icon}
 "Bloons TD 5"){kind=icon}
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