I finished the game! I really enjoyed it. I have some feedback:
In build mode, we can build using both mouse clicks and the WASD keys. However, since WASD doesn't support diagonal input, I find myself clicking to build diagonally anyway. If we’re already clicking for diagonals, it might be easier if building was just click-based.
If building becomes click-based, the WASD keys could be used for movement even in build mode. This would make building feel a lot smoother. Also, I think it would be helpful if we could build things you can stand on (like traps) right at our feet.
Anyway, thank you for making such a great game!