Bowser's Third Castle
When you find ALL the glowing rabbits you get behind the door and get a star. But if you go in again you will here boos
if you captured all the rabbits they will give you a key to open that door and that door contains a star
Walk into the mario door.
If you mean that door in the rec room in Super Mario 64 DS with the number 8 on it, you just need to get 8 stars and then it will open. The course with Goomboss, who holds the key to the room where Mario is locked, is behind this door.
it is in the castle's basement in the star door behind the slide. get turbo fludd to get up it. it is possible. I did it once myself.
Well, you go up the elevator and go into the door. The door leads to world eight, where you fight the final boss and retrieve the last star.
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waluigis not in the game
You will have to speak with Toad to unlock a quest in which you catch rabbits. Once you have completed this quest, you can use the white door for Super Mario 64 DS.
Simple. Press the spacebar when you are in front of a door.
You will have to defeat Bowser in the Dark World...then go downstairs to where the Big Boo was...& look behind you to find a door. Inside, look for a door with a star on it & the portal there will take you to Hazy Maze!
u dont...peach floats down from there when u beat bowser in the mystery of the never-ending-stairs...or the final challenge.