Ancient Core

Ancient Cores are items found in Breath of the Wild.

"This crystal was made using lost technology. At one time it was the power source for ancient machines. This item is very valuable to researchers." — In-game Flavor Text

Description
Ancient cores are a rare drop by Guardians. They can also be rewards for clearing a shrine. They have no value for cooking and restore no hearts. However, they can be used to make Ancient items at the Akkala Tech Lab. They can be used to upgrade various Runes and create Guardian resistant Armor and Ancient Weapons. Another variety of Ancient Cores are Giant Ancient Cores. These are very rare drops from Guardians and can sometimes be found in Shrines. They can also be used to craft Ancient Weapons and when cooked with a fang of each of the three Dragons, can produce an Ancient Guardian Key that allows Link to control a Guardian.