Nice to see a fellow Godot user :). Loved how you incorporated the theme into the game, but right now the upgrades don't seem worth it at all. I got to wave 8 without any upgrades, just holding right click and moving side-to-side, before an enemy went off-screen so that I couldn't shoot it and got stuck. I can see some potential though, I really like the turrets and how they can also hit you, but maybe you shoot also be able to destroy the turrets. I didn't use the ice bomb because I don't know how to activate it.