The levels were well thought of comprimising of a new enemy each level.
Liked the variety thought they were challenging at times.
The boss was cool too.
I can't really think of anything bad about this game, would have been challenging if you had of included a obstacle like a block or two or three in any level past 10 or the last three levels when you pretty much have all the upgrades or close to it. Would love to see another one, possibly a boss every few levels or some mid boss like enemy with the robots per level.