Congratulations! You just won the I Won! I Won! At Pirate Defense Badge and 30 points!
Seems extremely difficult until you find a good strategy at which point it becomes tediously easy.
5/5 for originality and effort, though
4/5. Good concept, great art, just the right amount of challenge to frustrate me without making me give up (level 17 and 19 were the trickiest). Lots of people are going to say it's "impossible," but it's nice that it takes a certain level of skill and perseverance to complete.
First of all, good concept, excellent start to a TD game. Very rough around the edges but the core is there.
Suggestions: Different kinds of units i.e. more variability to make things less predictable/repetitive (certain units could be strong/weak against certain weapon types),
Different kinds of terrain, again for variability and to keep every level from being the same,
Either an upgrade system for the towers or a branching system e.g. choosing to turn a tower either into an artillery or a gunner,
Options menu with graphics/sound options,
Difficulty levels,
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