couple problems
a few moderate problems which stood out for me after 20 minutes of play:
-you can't click on enemies that are passing through the little death animation of another, which means you have to wait a second before you can attack the next overlapping dude right beside the castle
-blue bold writing on a white background is not a good idea. please, change the colour and font of the menus
-can't see what runes I have
-archers and gunners don't do much - have them actually fire stuff instead of giving them a random chance to hit a random enemy.
-upgrades are in very small increments, menu that pops inbetween levels is awkward to navigate and feels cramped
This game is alright how it is, but it could be a lot better. Please feel free to PM me and I can expand on these suggestions and maybe offer a few more.