Had a blast playing through this! The difficulty curve is solid, with the first level giving you just enough a chance to experiment with how the game works, and building challenge from there. I kept finding myself barely beating stages, which was super satisfying.
My only critique would be that it would have been nice to have an indication of enemy range, as well as a clearer indication of player range (moving the mouse towards the player wouldn't always turn the cursor yellow by the correct tile).
But overall, once I got a grasp of how things worked, I had a lot of fun with this game! Nice job with this one!