Answering some frequent questions here:
1- Hydraulic is NOT available in Kongregate, only in Armor Games & Newgrounds (I don't know about other sites).
2- The two secret zones are available only in Heroic difficulty. Challenging difficulty gives you access to the first secret zone only.
@ Dogwai: to get to the extra zones u must play in heroic. If you play challenging you'll get access only to the first zone, and easy gives you nothing.
I can't get past mission 7 (because one of the "OK" buttons that shows new units won't dissapear) and my game won't save, so I have to restart it hundreds of times. Fun game, but this took it all away. 2/5 Hope that I can improve that.
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