Leo, did you know? You can unlock Ghost Houses in Super Mario Bros. One! All you have to do is, kill yourself 25 Times on Level 8-2! Then that will unlock the 3 secret Ghost Houses! The First one has lots of Koopa's for some reason? I don't know why not Dry Bones? Anyways! To unlock the 3 Ghost Houses kill yourself 25 times in Level 8-2! Its really well hidden!