Now let's go all the way to the north, where a few people told you about a forest and the famous sword that seals evil. Warp to the Eldin Tower and jump towards Hyrule Castle. Glide from one mountain to another, then keep going on foot until you reach the...
Woodland Stable
Talk to Ashe and ask him about the surroundings. The Hyrule Field is south from here, while the Great Hyrule Forest is to the north, also called the Lost Woods, where a furious wind pushes people away. Talk to Molo who heard about some docks north of the castle and to little Shamae who wants to see some balloons fly into the sky. You find again the merchant Beedle and the painter Pikango. Take the Double Axe lying around if you need it. As you've probably seen it, there is a shrine nearby, so go east.
Mirro Shaz Shrine - Tempered Power
Go right, wait for the lift to come and go down. Take the Iron Sledgehammer from the chest, then stand in front of the orb. Freeze it with Stasis, then hit it five times while standing a little to the left to send the orb straight ahead into the container. If the orb falls into the water, hit the switch on the right to start again. Go into the next room, freeze the stone block, then hit it four times so the seesaw is correctly positioned. Quickly climb one of the ladders (or freeze the seesaw), then run to the top. Go left, go down with the lift, then open the chest if you need another Iron Sledgehammer. This time again you have to send the orb into the container at the back of the room. Proceed like beforehand, or place the orb further back and one slab more to the left, then freeze it and hit it as many times as possible while aiming at the container. The orb should rebound into the water and fall into the container. Find a Giant Ancient Core in the now reachable chest, then use the lift again. Look at the Sheikah symbol and the monk Mirro Shaz gives you another Spirit Orb.
Go back to the stable and look at the signs near the fire pointing towards Hyrule Ridge to the west (as well as Zora's Domain and Akkala to the east). So go west while picking some mushrooms and some Bigh Hearty Radish in the grass. On the right, you can attack the Bokoblins by starting shooting an arrow at the beehive. You reach the Rauru Settlement Ruins, where travelers are attacked by monsters. Fight them, then talk to Mils and Mina who give you some food. Then look to the right, you see another Sheikah tower. Go in this direction and you will reach the Military Training Camp. Fight the Bokoblins, shoot an Ice Arrow at the flying sorcerer if you meet him, then go round the tower from the right side, go up the path then glide towards the watchtower.
Woodland Tower
Go ahead, fight the Moblin, then pick up some Bomb Arrows from the chest. Go behind the watchtower's fence next to you, then climb it. Hit the Bokoblin, climb some more, then fly to the tower and climb it. Place the Sheikah Slate on the terminal to get the map of the area. Now glide towards the Minshi Woods northeast, then follow the path going north until you reach a weird ambiance at the...
Lost Woods
Follow the torches until you reach a big tree, then go right where you can see another torch further. Then slowly walk west. If you ever see a bright white light, backtrack quickly or else you'll leave the woods. Inside a hollow tree, you can find a chest containing a Topaz. Keep going northwest where you can find another chest inside a tree containing some Wooden Arrows. Then, still going in the same direction, go between two tall rocks and you'll reach a clearing. Go straight ahead to the Korok Forest! Go ahead again and there you see a sword into a pedestal! Pull it and you'll have another short memory of Zelda. Then the giant tree in front of you starts talking.
It's the Great Deku Tree, who has been waiting for you for a hundred years. The sword was created by the ancient Goddess, it's the sword that seals the darkness that only the chosen knight can wield against Calamity Ganon. But to take out the sword, you'll have to get your full strenght back, which means having at least 13 red hearts. If you have them already, take out the sword from its pedestal, otherwise go on reading.
Look on your right, Hestu has found his way back and is now staying there, talk to him to exchange Korok Seeds for new pockets for your pouch. Next, talk to Chio, the Korok in front of the Deku Tree, to learn that Koroks have prepared trials for you in the shrines inside the forest. Talk to Kula on the left who asks you to show him a rod with the power of ice. Go inside the Great Deku Tree and talk to Maca who has a lot of interesting info. Inside the tree, Peeks would like to see a Blupee. Talk to Pepp next to the bed who says you are in the Great Deku Tree's Navel and that you can sleep and recover all your hearts as many times as you want. At the Spore Store, Natie sells mushrooms and at the General Shoppe, Daz sells food and arrows. Leave, go northeast and you quickly reach a shrine...
Keo Ruug Shrine - Fateful Stars
Start by reading the stele at the top of the steps which talks about stars. It's referring to the kind of constellations on the back wall, as well as on the two on the left and the two on the right. For the left side, back row, you can count 5 identical constellations on the back wall, and for the front row, there are 3 identical constellations. So you have to place the orbs in the 5th container (according to the number of lanterns) for the back row, and the 3rd one for the front row. Same thing for the right side, you have to place the orb in the 2nd container for the back row, and the 1st one for the front row. Go through the bars and notice a chest on your right. To get a Knight' Claymore, you have to do the same thing according to the constellations on this side of the wall. On the left side (with your back against the entrance) 4th container for the back row and 2nd one for the front row. For the right side, 1st container for the back row and 2nd one for the front row. Then, look at the Sheikah symbol and the monk Keo Ruug gives you another Spirit Orb.
Go back near the sword and take the path going northwest. In the fog, talk to Tasho on the left who is worried about his friend Oaki. You have to follow him from afar but without losing him. Beware, Oaki stops sometimes (when he's talking) or he looks behind. If he's wondering, crouch so he goes on. Finally, he reaches the shrine and you can then go in without worrying.
Daag Chokah Shrine - Daag Chokah's Blessing
Go forward and open the chest containing an Ancient Core, then simply receive a new Spirit Orb.
Go back near the sword, then follow the sign pointing to the Test of Wood and the bean-lanterns. Talk to Damia who starts the trial. You have to find the shrine without breaking or un-equiping the Forest Dweller's Sword, Shield and Bow he's entrusting you. Unfortunately you have to give up on some weapon if you don't have room in your pouch. Go straight ahead and since you musn't break the sword, use bombs when you can. Drop a bomb near the crates on your right, then keep going that way. Use the Bow for the skeletons above and for the Octoroks when they jump out of the water. You mustn't touch the muddy waters, so when you reach that place, use the Cryonis Rune to create ice pillars and keep going until you reach a chest containing another Forest Dweller's Sword. Finish to cross the muddy pond, then when you see two damaged barrels in front of you, look at the tree on your right and find 100 rupees in the chest. Use Cryonis again to cross the following pond, and you reach the shrine.
Maag Halan Shrine - Maag Halan's Blessing
Go forward and open the chest which contains a Giant Ancient Core, then receive another Spirit Orb.
Go back once more near the sword, then follow the path and the lanterns going southwest. Talk to Zooki on a rock who gives you a hint about the trial: "The hungry trees will show you the way. Spy their iron to win the day." So, use Magnesis on the tree trunks around you and go in the direction of the ones with a metallic item in their "mouth". Keep going like this through the forest, until you find a rusty shield on a rock. Grab it with Magnesis and place it into the mouth of the tree surrounded by two torches (as the stele asks you to). A chest appears within another tree and you can see the next tree to reach. Find some Amber in the chest, then grab it and place it on the raft nearby. Go on the raft, drop one of your weapons on the latter (if your pouch is full), pick up a Korok Leaf in the water, then move the raft to the torches-tree. Drop the Leaf, pick up your weapon, then place the chest into the tree's mouth, which makes a new shrine appear...
Kuhn Sidajj Shrine - Kuhn Sidajj's Blessing
Go ahead and open the chest containing a Giant Ancient Core, then receive another Spirit Orb.
Go back once more to the sword and talk to Chio again. As a reward for your deeds, he gives you three Big Hearty Truffles and says that you can try to take out the sword again. In order to succeed, you have to have at least 13 hearts (which is the case if you succeeded all the shrines in the regions already visited in this walkthrough).
After brandishing the Master Sword, you see Zelda in front of this sword talking with the Great Deku Tree asking him to deliver you a message, then she sticks the sword into its pedestal. Then, the Great Deku Tree says it's the sword you used against the Calamity a hundred years ago and that the princess is still in Hyrule Castle where she's waiting for you.