Needs a bit more... finish, polish maybe, animate the water in the first level, take away the stroke from the text in the boxes, make towers red when you can't buy them, you know, usual tower defence features, this isn't terrible though but it's bad.
Honestly quite bad. All that seems to work is adding mountains to the land. Nothing else has any effect, no matter the order. I think the concept itself is good though, try again maybe?
Good luck! :)