Maybe the coolest thing about this game is that a few levels were designed really well. If you do the thing every other tower defense game strategy involves, you're just going to cluster a whole bunch of towers. One level in particular was set up so if you used obvious tower placement, the enemy would rush you mid-level and no matter how many towers and upgrades, you'd get overrun. That's great strategy game mechanics for a TD game, and I've played many.
However, game balance was a bit weird. Normal difficulty was impossible, easy was (after a few $ and element upgrades) much too easy. Especially with the pet that makes flying creatures land.
Everything else has already been said. Graphics are great, gathering coins and elemental items is great. This has all the makings of one of the best flash games on the Internet and to finally beat out Don't Touch My Gems.
User Thomasfurious said it all: this game is not well balanced and easy to beat with upgraded air units. Points for creativity, features, and cool stuff behind the scenes, but once you figure out the reliance on air units, its easy to beat.
Not really a mature tower defense game: a "speed up" button, more than one specialized unit, some sense of what the attackers look like and how to best address that as the game goes on. Strategy, like the genre says. Still, kudos on the smooth look and feel, story, and simplicity. Big points for making interest on unspent money, dangling greater rewards for not going all out on upgrades. That's a new one in TD games and a cool idea.
5 stars -- excellent game I've really enjoyed playing. Minor issues: I was disappointed that the game balance seems to be focused primarily on creating a maze for creatures to walk through rather than on effective/strategic upgrades. I'd like it to be a combination of both so that you create the maze to give more powerful units more time to work on the invaders. There were also a lot of towers that didn't seem to be particularly necessary to the game itself -- they felt like afterthoughts, especially when many levels really just called for the basic level 1 tower.
Played a lot of games before and since that really haven't matched up to the quality of this release. Really the definition of a 5 star flash game along with Cursed Treasure.
One negative: I've played this game on very fast computers and had some issues with the action happening TOO fast, which increases the difficulty quite a bit.
A lot of fun. However, there are some suggestions I'd like to add for future games:
Different types of monsters that require different strategies and preparations before every round. Right now this game is really just attrition: you just shoot everything. For example, a very fast enemy that's hard to stop would require some type of defenses set up between rounds. A very slow enemy would require sustained gunfire. Flying enemies could poison your character, etc.
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