This is simple, fun and has many different stages to play. might want to add a simple AI just in case if the player is just alone.
I find the most creative part is allowing the player to hold down a button to slow down aim which brings out the simple factor. Overall 5/5 fun for me.
Just a nitpick, u might want to reduce the number of rotating objects from 4 to 2 on the outer square to give the player enough time to react, otherwise it will be punishing to the slower reaction player.