I found it rather easy. I was able to save money each level and buy when the tough ones came. In total I built three pistols two lasers a multi and a bomb. Mostly to see how they all worked. They never made it more than half way.
I would suggest either making some of the monsters a little tougher, the damage lower, or the cost for upgrades higher (or all three). It would be nice it there were more "effect" towers (slow, fire, splash), or weighted towers/monster combinations (such as vectorTD).
I thought overall the game was well made. I didn't have any drop in gameplay when there were a lot of monsters or anything (which seems to be a problem for a lot of people). A good start, I look forward to seeing how you improve it.
Great game, but I have a couple of complaints.
1) I agree with the "spawn corner". You should have something to announce a ball's entry..
2) High scores are difficult to read, they overlap the date (I am running Ubuntu/Firefox).
Otherwise, I love everything else.
A pleasure from beginning to end. 5/5.
I did notice one thing....there is a spot where you can see then edge of the graphics. On the other side of the river, underneath the fishing caveman, look at the bottom right.
Pretty well made. The power-ups make it really interesting. You might want to track how long as well and score that. Once you get that gravity low, there are some long times to wait (a visual distance cue would be nice, too--like an arrow).
I see a few problems. It seems very easy to get stuck in places, like bouncing between bumbers or falling under the flame (and I couldn't kill myself!). I change it to count the number of lives it takes, and that would help users gauge their success.
Overall a good game. The controls are responsive and the basic gameplay is good. The graphics are not bad; I like your player char.
I agree with Shioran that all the mental stimulation is based on remembering the layout and trying to turn it to the correct position. It would be cool if you had to throw a switch in one position and rotate to another to get out (or collect keys or something). Something else you might consider adding is dying if you fall too many levels. Then it would get frustrating.
That was refreshing change from the standard asteroids. Lots of nice power-ups, but you make the user decide. I like being able to play on my strengths.
Can't think of any negatives. Good job!
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