You beat every single level worlds 1,2,3,5,6,8 and these you don't have to beat: worlds 4 and 7.
secret exits
if you mean new super Mario bros, then you beat world 6 castle when you are mini Mario.
Mario Bros. Super Mario Bros. Super Mario Bros. 2 Super Mario Bros. 3 Super Mario World Super Mario Land Super Mario World 2 Super Mario Land 2 Super Mario 64 Super Mario Sunshine New Super Mario Bros. Super Mario Galaxy New Super Mario Bros. Wii Super Mario Galaxy 2
New Super Mario Bros. happened in 2006.
Just beat 5th boss as Mini Mario.
die
beat world one.
beat world 6
New Super Mario Bros. happened in 2006.
Super Mario bros super Mario bros 2 super Mario bros 3 super Mario world super Mario 64. Super Mario sunshine new super Mario bros ds super Mario galaxy new super Mario bros wii super Mario galaxy 2 (any other games please check something else
You have to beat Mummipokey (the boss of World 2) as mini Mario.
You beat it.