To start, I am not making this up. This either happened or my memory is playing tricks on me. I never used a gameshark or similar device. So some 10-15 years ago I was playing a PAL copy Majora's Mask on the N64. After putting it away and not playing for a year or so I decided to play it again. I don't remember if the save file was already there or if I made a new one at the time. I started playing a save file which was at the very start of the game before you (should) have the Ocarina of Time. For whatever reason every item in my inventory was an ocarina. When I opened the chest containing Deku Nuts one of the ocarinas was overwritten by the Deku Nuts. After the scene when you meet the mask salesman I spoke to him right away and he taught me the song of healing without needing to retrieve the ocarina from Skull Kid. Whatever happened after this I don't remember. So in some rare cases can the save files in N64 carts become corrupt over time and provide interesting results such as this?