For hard, you want your forces to hit one side before the other - start with a monkey on the far left or right so he gets a full shot at each row of bloons instead of having to divide his attention. I go with two monkeys (full upgrades), then tack towers (fast shooting), then a cannon just before the lead balloon. Cannons after that, use road spikes to break black bloons.
Huh, I never tried to get behind the spinner. Its buddies always abused me to death before I could get that far. On Survival III I just ended up using freeze and acid on it, killed it pretty fast.
It crashed for me on Survival III just as I killed the spinner <
Needs some upgrades to you, like defense and healing. There should be some warning before the flyers shoot. And the spinner shoots too fast; it's nearly impossible to get away if it hits you less than a third of the screen away.
And I'd also suggest a square arena, instead of a rectanble, with the ability boxes NOT part of the arena; they cover up too much area at times.
Very good game, just needs some fine-tuning.
If the spinner wasn't the single most annoying enemy ever, this'd be 5/5. Seriously. Give some hints or something in-game, that thing has me swearing at my computer in Survival III.
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