3/5 because sometimes it seems like it lags. It isn't focus problems, but it won't move occasionally. I can't ever seem to get the super power thing to go off either. Really fun game, though!
Oh and would everyone please quit whining about the ratings. It's just a game, and it's just a website(an amazing one, though). There are more important things to do rather than whine about a game's ratings.
So I just finished the game. Glowing frame on everything. Once I fully upgraded the # of high grade starter gems, I got a glowing frame on my first try for every other level in the game.
Try to make lots of level 7 gems. They are strong, and they give HUGE point bonuses at the end. For bosses try to get purples and greens.
To beat the first epic level, I followed this:
http://www.youtube.com/watch?v=4gyJUjph2Hw&feature=channel_page
roughly, and when the boss came most of my gems(about 5) were level 5, and the rest(2 or 3) were level 4
But since we have no armor power up, what I did was once the boss got out of the range of the towers, I used ALL of the level 5s and 4s for gem bombs and I finally won
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