To stab things, hold L + Up and attack.
First Boss passwordIn the room before the first Boss, hit the enemies in this order: 2, 3, 1. In Master Quest, use 3, 1, 2.
Defeating the first BossShoot her in the eye when it is red. If you do not, her babies will attack you.
Angry manIn the castle garden, shoot the left window. A man will throw a bomb at you.
Mario and friendsGo to the garden in the castle. Go to the right and look in the window.
Bowser's faceLook at the object on Malon's neck.