Uploaded June 2014 | Updated September 2026, 1 week ago
For a while now it's been possible to dupe items by overflowing your key-item inventory past the 32-item limit. Upon doing so, new key items get added to your normal-item inventory for some reason, and then the game would always ask you to throw a normal item away. The item that you throw away gets duped, unless you already have 10 items. It was thought that the overflowing of your key-item inventory is what caused the duping to occur, but then I realized that that might not necessarily be the case, and that I already knew how to test the theory.
The item-duping glitch is ACTUALLY caused by throwing away an item while you have less than 10 normal items in your inventory. Overflowing your key items is one way to cause this to occur, but here's another way: Have 10 normal items, and then, exactly 2 frames prior to obtaining an 11th item, open your items menu and eat something. Between the time you select to eat the item and the time you actually start eating it, the 11th item is obtained and the game displays the "you need to throw something away" message. Wait for the item that you ate to be fully consumed, and THEN open the dialog to throw an item away. Now you're being asked to throw away an item, while you only have 9 items in your inventory. Throw away an item from your inventory and it will remain there and also be thrown away for you to recollect. For some reason, when you do this, the item doesn't wait for you to acknowledge that you're throwing it away before it just starts flying. There's also a side-effect where, if you don't dupe the top item, the item above the one you dupe gets mysteriously deleted.
The glitch that has resulted in this item dupe has been known about for a long time, but it was thought that all you could do with it was eat an item and then recollect it afterward. That's what occurs instead if you open the menu 1 frame before collecting the item, or if you open it 2 frames before but then open the throw-away dialog too early.
Item duping is currently banned in the 100% categories because of how it can be used to dupe Letters for Star Pieces. I think the definition should be changed to ban key-item duping only (if anything really has to be banned at all) and allow this to be done as it surely saves time over farming coins from Smash Attack and can't actually be used to circumvent the categories' requirements. It might also save time by skipping having to hit that block in the desert 100 times for an Ultra Shroom, for example. I could see it also being used to get extra Repel Gels in any%.
For a while now it's been possible to dupe items by overflowing your key-item inventory past the 32-item limit. Upon doing so, new key items get added to your normal-item inventory for some reason, and then the game would always ask you to throw a normal item away. The item that you throw away gets duped, unless you already have 10 items. It was thought that the overflowing of your key-item inventory is what caused the duping to occur, but then I realized that that might not necessarily be the case, and that I already knew how to test the theory.
The item-duping glitch is ACTUALLY caused by throwing away an item while you have less than 10 normal items in your inventory. Overflowing your key items is one way to cause this to occur, but here's another way: Have 10 normal items, and then, exactly 2 frames prior to obtaining an 11th item, open your items menu and eat something. Between the time you select to eat the item and the time you actually start eating it, the 11th item is obtained and the game displays the "you need to throw something away" message. Wait for the item that you ate to be fully consumed, and THEN open the dialog to throw an item away. Now you're being asked to throw away an item, while you only have 9 items in your inventory. Throw away an item from your inventory and it will remain there and also be thrown away for you to recollect. For some reason, when you do this, the item doesn't wait for you to acknowledge that you're throwing it away before it just starts flying. There's also a side-effect where, if you don't dupe the top item, the item above the one you dupe gets mysteriously deleted.
The glitch that has resulted in this item dupe has been known about for a long time, but it was thought that all you could do with it was eat an item and then recollect it afterward. That's what occurs instead if you open the menu 1 frame before collecting the item, or if you open it 2 frames before but then open the throw-away dialog too early.
Item duping is currently banned in the 100% categories because of how it can be used to dupe Letters for Star Pieces. I think the definition should be changed to ban key-item duping only (if anything really has to be banned at all) and allow this to be done as it surely saves time over farming coins from Smash Attack and can't actually be used to circumvent the categories' requirements. It might also save time by skipping having to hit that block in the desert 100 times for an Ultra Shroom, for example. I could see it also being used to get extra Repel Gels in any%.
