I see.... bug: If you build 2 things near the enemy entrance, and at the second one you get a message that you cannot build it, then you won't be able to place it anywhere.
I played this game on newgrounds. I must say that the hero thing is a great improvement to your game. My suggestion is that next time when you make a game, put it on fgl.com There are lots of testers, including me, that give great feedback. The game is good, but I find the UI art quite bad. Units are great, the concept is great. You could add some nature animations, some powers, the hero could be controlled via arrow keys and shoots via space-bar. I like the upgrades, and I can see that you worked a lot at it. Great job! (but needs improvement :) )
If you took this game believing that you could do because it is written "Add this game to your webside", you should think that this is not your webside, you are just using it.
I would suggest different colors, other form (instead of a boll, you could put a chicken or something to animate) This game is.. something like.... 30% complete.
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Thanks for your feed back. Definately needed to test it more, will learn from that. Appreciate the positive comments too :)