Interesting concept, but the problem is that the only your defence is the house or VERY SHORT-TIMED shields. So, you sit behind the house in safety because tornados don't go behind house at much, or you try to play the hardest ever rhythm-game ever by spawning shield a milisecond before log hits you. I think, you could add some buildable obstacles, or give player something of a parry. Or let the player hold the log to defend themselves.