Clunky, Badly designed and poorly executed.
I'm not sure where to begin. I'll start with the most glaring flaws.
Graphically its one of the most poor games I've ever. It has no coherant aesthetic and shifts between graphical styles every level. Which is fine, but the graphics themselve are very, very bad. Badly optimised, badly drawn and ripped. Just bad. Everything about the graphics in this project are very amateur. Have a coherant overall aesthetic or a coherant aesthetic for each level. You can't just throw artwork together and call it a game.
No backgrounds in the levels is a good thing and a bad thing. A simple muted background for each level could add to the atmosphere as long as it isn't too noisy and pulls the viewers attention away from what they're doing. It should be funtional like a black background, but pretty like wallpaper.
The interface is good though. Non-intrusive and functional without being over flashy. The font for the score throws everything out of balance though and detracts from this.
retry, stage select, play more and next stage scream amateur once again. Those should be capitalised so that they read - Retry, Stage Select, Play More, and Next Stage. I'm not the king of grammar and spelling. But glaring flaws like this detract from the games quality.
Music - Slightly in tune with the game, but feels tacked on. Perhaps more appropriate music could be chosen. Not much to say on this. It works for what it is.
Gameplay: The part that I actually liked. I enjoyed the challenge, it was fun and varied, always keeping me on my toes. The graphical and aesthetic problem really took away form it however. The difficulty scaling was out of whack, some levels were simple and some levels were unfairly hard to the point where it was luck to win some - I'm looking at you spaceship level. I had to wait nearly 5 minutes for the last spaceship to actually start coming onto my screen. This shows me that you did not properly test your game and just threw it together. At no point should a player be relying on luck in a game IF the basis of the game is a not a luck based challenge. Honestly, it plays like a proof of concept than a real game. I did really enjoy the variety and complexity of the levels, and they were quite easy to figure out what to do, but a little more challenging to do it.
I'm not going to bash you for having no storyline, as it doesn't need it.
Overall, what you have here is a fantastic IDEA, but a bad game. It needs work and a lot of it if it is to be a fantastic game. I really look forward to seeing a sequal as it has bukets of potential, but is overall not up to scratch with good game design principles.
