While I'm necroing, this is for anyone about to make a rating. These can be useful in levels where you would give lots of handouts or rewards if the right block is selected, which is only one example. This block is good for trickery, and that can be incorporated several ways. Not all games are hard all the time consistently, and not every hack is Kaizo.
Set it to look like a real 3-up moon for extra madness. Best results, if lives are extremely valuable in your hack. Another idea is to put a bunch of those evil moons in a pit so one who falls into it will lose 15 or more lives or get instant game over, losing massive chunk of progress.