I liked this game a lot! Like some others have mentioned though, it get's a bit grindy at times, and I would have liked it to be a bit longer with a bit more variety, but I thought the mechanics were great, the action was exciting, and it was one of the few arcade-style games that I actually enjoyed in quite some time!
First off, I thought this was a beautiful and fun game - I liked the basic mechanics, and had a fun time playing. Also figuring out how to defeat the bosses was intersting.
That said, I think the weighting was a bit off. I had to grind the first level to make it past the second, but once I got to the third level, the rest of the game was much easier. In fact, I don't think I died once after the first row! The amount of gems you get barely goes up with the levels, and the upgrades don't require all that much money - I focused on the money skill and regeneration powerup, and after that things became way too easy.
Also, some of the levels on the last row were just super slow too - I think it was United Battleships and United SHooters; I spent a lot of time just waiting for them to materialize, and then one hit with my quad damage laser finished most of the enemies off.
I still finished the game, because like I said it was gorgeous and fun, but it does need a bit more of a steady challenge
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