After getting a total of three stars, enter the room with the painting of the sunken ship. Turn to the left of the entrance. Once in the room, press (C-Up) to look around. Look carefully to see a black square in the wall near the ceiling. Perform a double jump and climb into it. An extra life mushroom will come out. Note: Make sure to choose the square to the left of the entrance. The one on the right will lead you to the Castle's hidden aquarium.

After emptying the moat in front of the castle, use the ramp to walk down into it. Go under the bridge and press (C-Up) to look up to see two yellow coins. Perform a wall kick to get both the coins. Once you get both coins, an extra life mushroom will drop from above. This trick takes practice, and you may want to do a double jump and then a wall kick, as the coins are very high.

Use the following trick for another way to get the two yellow coins. If you have collected all 120 stars, cannonball yourself to the top and get the flying hat. Jump of the castle and fly under the bridge to get the first coin. Swing around in order to get the last coin. Then, pound ground to land so you can get the extra life.

Go to the first door on the left in the castle that does not have a number on it. Enter it and jump into the painting. Select any level and go to the cannon by the Chain Chomp's territory. Jump onto the tree just behind it, then do a handstand to get an extra life.