Really quite nice, short and sweet! Your choice of audio doesn't detract anything from the game either, not bad at all.
If I had any recommendations for you, it would be to increase the task and health visibility, as well as to possibly add some more challenge to the game. It was certainly a fun take on "spot the difference", but I do wish there was a bit more.
Either way, what you did manage to put together this time around was really solid. Nice work! ^^