Equip a bow and any set of arrows, then draw your bow back. While it is drawn back, go to the inventory screen. Select the arrows that you are using, then go to the item to be duplicated. Drop the item, then leave the equipment screen and resume the game. The item that you dropped will be duplicated. You can pick up all the duplicates and use or sell them. The amount of copies of an item you make depends on how many arrows you have equipped. For example, 10 arrows allows 10 copies. This works with most, but not all, items and weapons. Note: Do not try to duplicate more than 250 copies of an item or the game may freeze.