Very neat game. Although the control's plenty intuitive, the presence of a tutorial definitely helps. I especially love the polished touches here and there, like how sometimes tiles lights up or how the resources meanders about.
If there's a low-effort thing I would add, it would be some dialogue / narration as you fight the boss. Just a dialogue bubble to urge you to quickly finish him off / give context to why you are doing this / even some humor like nagging you when you damage the shields instead of the boss.