there is a key on each level if you get one it brings you to the next level if you beat all of them you get to the special world not many people know about this world but if you want to see it for yourself look it up on YouTube
use fire ball ,JUMBO MUSHRUM, or just use shell Mariothere is an earier way just jump over
it if you cant do that you lose a life
There is NOT SUPER MARIO WORLD Wii...
Beat the world 2 boss as Mini Mario.
if you mean new super Mario bros, then you beat world 6 castle when you are mini Mario.
Beat world 3
you win the game In super Mario world 2 you go back to main map
Beat Petey Piranha as Mini Mario.
if you mean ds,beat world 2's boss as super mini mario.
Beat world five's boss as mini Mario/Luigi.
Beat world seven.
Beat world 2.
beat the castle in world 1
beat the sunken ghost ship