This stuff DEFINITELY needs to be explicitly explained. I saw the "Romeo and Juliet" stamp and figured if I saw a 9-square I should just leave it alone O_O
The monsters don't "behave" either. They either die or kill you when revealed. I didn't even know that the direction they were facing was important! I just thought they looked in different directions for variety's sake.
I would never have guessed the guy holding a magic dark ball was a "mine master" and did something special if you killed it.