I like the concept of the game, never seen a tower defense implement new pathfinding if the certain path is blocked, could make for some interesting levels.However the game, it's just terrible for an alpha, it lacks features like upgrading towers/unique enemies and, most importantly levels.It still needs some work.If you're ever releasing an alpha of anything, make sure it contains the core concept and some levels so you can introduce the certain mechanics, this is more of a test than an alpha game.