Tip: If you get the hammer + max stun duration, you can easily do survival to lvl 90+. Just aim at one of your mushroom patches, charge up your hammer to the max shock radius, and let it rip. If you have no delay in between strikes, nothing will get past your defense. Don't panic if a bird gets a mushroom in between your strikes, you'll get it as it flies away.
There is a rare occasion that a perfectly timed bird will snatch a shroom, but the chances are around as high as you accidentally smashing a spider.... convenient. ^_^ Hope this helps!
Easy Strat: Max out a warder so it runs like a beast. Ensnare everything with nature's grasp before you go arrow crazy on it with steady shot.
For the final boss, nature's grasp him, then shoot shadow arrows, then explosive ones. Kills all the guys while constantly damaging the boss. Didn't need any potions. =)
Ok, so the issue with upgrading the heroes is that you can only level up heroes that are in slot 1 or 2. None of the other slots work (as in, you can't click on the hero). That's my experience anyway. Pretty good, not necessarily ultimate, but hey, it's a good game.
Fixing the auto-fire error:
If you're experiencing the game freeze after you hit the alt key, for certain browsers, you just need to click on the game again somewhere. The game should continue as normal.
Auno, I was freezing as well, and it happens everytime I hit alt, but I think it just makes the flash player inactive or something, so when I click anywhere on the flash screen again, things start moving again, and the auto-fire is on. =)
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