Nice game! I love how you've flipped the concept of a tower defence game, it definitely feels different being the attacker instead of the defender. I like how the towers upgrade as well, it was a good incentive to play quickly (and it was fun shooting them down too). The variety in weapons was also good to see - I'm not sure if they actually did anything different, but it was still interesting! It'd be great to see different effects for each tower, different mechanics for all of them, I'd love to see that depth added. Good work on this game!