Play as Luigi:
The first step is to beat the game. Then go to the Special World 1 and beat the castle. Luigi is unlocked at this point. Now anytime you touch the screen below the world map there will be an “L” in a circle. Tap that L and play as Luigi.
Grey Tanooki Leaf:
While in the Special World you are able to grab Tanooki Leaves. These leaves appear as gray. You will know you have it when the bandanna around your neck turns either red or green. With Tanooki power you can turn into a statue when you put in the input for a ground pound.