You must collect all 150 stars, then it will automatically open.
To get on the castle roof of the castle
You will need to collect all 150 stars and the cannon in front of the castle should open and then all you have to do is go in the cannon and blast off.
To get to the top of the castle on Super Mario 64, there are two ways. The first is to get a running start (running towards the right side corner of the castle), jump on the castle wall, then on the grass, then back on to nearly grab onto the edge, and get on top of the castle. The second way is to get all of the stars, then a cannon will be accessible out on the front part of the castle. Then, climb into the cannon and shoot yourself on top of the castle.
get all 120 stars and go out side go to the cannon lauch to the top of the castle stand right in front of Yoshi press b and u get 100 lives yay its a me Mario
You have to fight Bowser 3 times before you can win Super Mario 64. When you get there, you have to hit Bowser 3 times. After you hit him 3 times, you will rescue Princess Peach/Toadstool. When you hit him 2 times, he will transport into a star shaped room, where there, you will have to hit him even harder. After that, collect 150 stars, and defeat Bowser AGAIN, then you will unlock a cannon that is placed in front of the castle. After that....... CONGRATULATIONS! YOU WON SUPER MARIO 64!
When you collect 14 stars, unlock mario. a beam of light will appear in the main room at the front of the castle, zoom and look up. You will then be flying. There will be a castle tower in the center of where you are flying with a giant red switch. go down there and GROUND POUND that thing. All the boxes should turn solid.
Lanches you onto the castle roof.
get all of the stars
you go in peach's portal in the front of the castle and the 2d black box
They appear randomly. The easiest way to get them all is to be Yoshi & walk out the castle front door & check for glowing rabbits. The locations for Yoshi in the front yard are: Where the water used to be on the right of the castle, beside the tree on the right of the castle, 2 are in front of the main door, & close to the garden maze.
you get it by hitting the red blocks you unlocked...if you didnt unlock the blocks,keep getting stars(get about 8)go to the main room of the castle(the first room you are in when you get through the front door)you will see a light.go under it,look up,and now you are flying.land on the platform in the middle of the stage and jump on the huge red switch. p.s.only Mario can do the job
You unlock Petey Piranha by completing the training on all 3 modes. You Unlock Boo by getting 50 or more badges You unlock Shadow Mario by completing ring shot mode You unlock Bowser Jr. by Completing all the birdie challenges (9 front, 9 back & all 18)