Vah Naboris, Divine Beast of Thunder
Shoot an arrow at the Guardian, run to it and hit it, then pick up its Ancient materials and its Guardian Spear if you want to. Go behind the hole, climb the slope and shoot an arrow at the eye so the pink substance vanishes. Go ahead, notice the electric device, and go forward where a chest is hanging. Use the Stasis Rune to freeze the chest, then quickly, cut the rope with an arrow, then when the chest is about to fall down, use Magnesis to grab it and pull it to you. Open it for an Ancient Core, then come back inside and climb the slope on your left. Place the Sheikah Slate on the terminal to get the Beast's map. You hear again Urbosa's voice telling you to activate all the control terminals marked on the map.
Turn around, jump further, the main terminal is in front of you. Go left, then right and attack another Guardian. Pick up its Ancient materials and its Ancient Battle Axe if you want to, then turn around, go straight ahead, enter the Beast on the left and find five Bomb Arrows inside the chest. Go back near the main terminal and get out from the other side. Fight another Guardian, pick up its materials, then go back inside near the terminal where you found the map. Take out the map, select the left pink dot (on the head's side), press A three times, then press B to rotate Vah Naboris 270 degrees. Go across the room and climb on the right on a path which is vertical right now. Rotate the same part of the beast 90 degrees and you can now see the terminal in front of you. Carefully go ahead, then hit the skull and shoot an arrow at the eye below, which makes the pink substance vanish. Go to the control terminal and activate it.
Look on your left, you see a chest. Rotate the central part of the creature 90 degrees, then glide to this chest and pick up an Ancient Shaft. As you've seen during the rotation, there is another chest right below. Stand at the edge of the platform while facing the main terminal, rotate this part 90 degrees again and while it's moving, go forward so you don't fall down. (If you ever fail, you can fly behind you on the left to reach the path above and fall next to the second chest.) Rotate this part 90 degrees again and the chest is in front of you. Find a Knight's or Royal Bow inside. Now you have to rotate the three parts of the Beast's body so the three circuits get activated (in green) on the ceiling, which will rotate a disk near its neck. Enter into one of the two openings in this disk and stay there to reach the top, then glide to the centre of this disk and get in a corridor. Go ahead while sneaking past the spikes and beams, then open the chest holding a Knight's or Royal Shield. Get out, go back into the disk to reach the upper level, then get outside. Jump lower towards the levers shaped like a cross, then slowly turn the lever clockwise to activate a wheel on the left on which is a light bulb. When the bulb is up, the light is on. Then turn the lever counter clockwise to light the bulb on the right. When the two bulbs are lit, Vah Naboris' neck rises and a lift gets activated. Step on this lift, then go forward and activate the second terminal.
Go back down and go back inside the moving disk. When you're at the top, fly to a platform on the green electric crystal's level, then go across the body and get out on the other side where are some connectors. If you (really) want an Ancient Gear, get close to an edge of the round platform and glide to a narrow ledge below you, then jump towards the Beast's body where a chest is, then go back to this place. Thanks to the Magnesis Rune, move the two upper metallic blocks to the left, and the two lower ones to the right, in such a way that all the connections are active and the rear part of the Beast rises. Then, you can climb the vines on the side, but the pink substance prevents you from going through. So select one of the pink dots and rotate it to cut the power and lower the tail again. Now, stand at the end of the tail next to a light bulb, then rotate the same dot to put the power back on and lift the rear part which now creates a bridge to Vah Naboris' back.
Go ahead, shoot an arrow at the eye as soon as it opens, then go on and get rid of another eye. Climb the vines close by to reach the back hump, then get close to another cross-lever and push it four times clockwise to light the bulb lower and activate a moving platform. Glide towards the bottom of the vines and go on the lift going down. Once you're at the bottom, shoot an arrow at an eye, then while staying on the lift, use Magnesis on the chest halfway up and drop it lower. Grab an Ancient Screw inside, then go back up and do the same with the electric ball on the other side of the chest. Leave the ball at the bottom, then go back up again and climb on the moving platform which will take you to the second hump. Fight another Guardian on another lift, then while staying on this lift, shoot an arrow at an eye to disperse the pink substance and clear the way to a terminal. Jump to this terminal when it's in front of you and activate it.
Go back on the lift and go all the way to the top where another electric ball is. Go on the moving platform to go back inside the back hump and open the chest which contains a Topaz. Then go back to the front hump, take the electric ball, climb on the lift and go to the bottom. Place the ball down, shoot at an eye to make some pink substance vanish thus creating a shortcut. Then use Magnesis on the ball to make it touch the bulb above the door to lift the bars. Get rid of the two Guardians, then notice the two pedestals on both sides of the bars. Go pick up the ball, put it on one of the pedestals, then go into the now accessible neighbouring room, grab the other ball and place it on the second pedestal. The bars being lifted, activate the fourth terminal, only one left!
Go back to the back hump, get out and jump lower. Move one of the connectors to lower the tail, then go ahead, go left (on the side of the remaining terminal), and glide to the ledge below along the Beast's body. Go forward carefully, fight the Guardian if you haven't done it earlier, then pick up its Ancient materials and its Guardian Sword if you want to. Backtrack a little and go in on the right. Get near the terminal, rotate the rear part 90 degres, then activate it. It's done! Rotate this same part 270 degres, then get out, go left and enter the main room on the left. For an extra chest containing an Ancient Gear, go back into the moving disk and when you're at the top, glide on the halfway up passage. Turn left, get close to the edge, throw a bomb at the round rocky part and blow it up upon contact, which frees an opening with a chest behind to which you can fly. Go back inside, then rotate the central part 180 degrees. Get close to the main terminal, place the Sheikah Slate on it and then Thunderblight Ganon barges in!
This boss is super fast! During the first phase, you have to avoid the green electric balls that he's throwing at you, then keep him in sight with ZL when he's moving really fast and be ready to hit him with your best one-handed weapon. If you manage to hit him, hit him as much as you can, then he'll fall on his back and stay stunned for a few seconds, rush at him and hit him again as much as you can. Repeat this a few times to weaken him. Be careful, if you get shocked, you'll drop your weapon and maybe even your shield, so pick them up as quicky as possible. When he has lost over half of his energy, the second phase begins.
Avoid wearing clothes containing metal, choose a non-metallic shield and your most powerful weapon even if it's a two-handed one. He charges on electricity and starts by throwing pillars at you. Stay on the move, then when the pillars start to vanish, use Magnesis on one of them and make it hover as close from him as you can so he electrocutes himself. When this happens, he'll fall down on the ground, then he'll throw electric balls again and will move very fast. Keep him in sight and hit him as soon as you can. If you have trouble doing so, don't try to get close when he's moving, let him come to you, raise your shield and be ready to hit. If you have Stasis +, try to freeze him, then rush to strike him. You can also eat a shock-resistant meal to take a little less damage. Repeat this tactic to defeat him.
Next, pick up the well-deserved Heart Container, then get close to the terminal. If you think you've found everything within the Beast, activate it. Urbosa then appears, she congratulates you and thanks you. She entrusts you with her power, Urbosa's Fury. Vah Naboris goes to settle at Spectacle Rock. You end up in front of Gerudo Town. If you've calmed down the four Beasts, you hear Zelda's voice saying that all Divine Beasts have now joined your ranks and all the Champions' souls have been freed. Go back to the palace. Riju is surprised to see you and says Naboris is no longer a threat. She entrusts you with two weapons Lady Urbosa used to wear: the Scimitar of the Seven and the Daybreaker.