The Hero’s Sword is the name of the side quest for obtaining the Master Sword and unlocking part of Link’s memory. The quest will begin as you enter Korok Forest in northern Hyrule.
The Master Sword is a legendary weapon and a recurring item in The Legend of Zelda series. It deals 30 points of damage, but will double to 60 when fighting Ganon and any monsters around Hyrule. Even though it has a durability, the Master Sword does not break in the same fashion as other pieces of equipment. After the swords breaks, it will reappear in the inventory after one day in-game time.
The Master Sword is located in the sacred Korok Forest. There is only one entrance and exit to this forest, and a maze must be navigated through to reach the Master Sword. The easiest method to find your way through Korok Forest is by following the trail of embers that are burning from the torches set up around the forest.
Once the Master Sword is located, 13 hearts will be needed to pull the sword out of the stone. The extra yellow hearts will not count towards these 13 hearts, meaning 40 shrines must be cleared, or a mixture of 26 shrines and the four divine beasts.