Fastest Way to Duplicate Items in Tears of the Kingdom using a Shield
If you are desperate for materials or rupees, here's the fastest way to duplicate items in Tears of the Kingdom using a shield:
1. Make sure you can perform a Shield surf which can be done by equipping a shield, holding the ZL button, and pressing X and A simultaneously.
2. While in the air, open the menu or pause the game with the + button.
3. Go to the materials list and find an item with only 1 in quantity, and HOLD it.
4. While holding that item, pick the four remaining items you want to duplicate.
5. Once Link is holding five items, exit by pressing the + button, and you will see the item Link is holding will be dropped to the ground.
6. As soon as you pick up the item being dropped, you will see that the last four things that Link holds are doubled.