This part will take you through the entire Goron Mines.
Inside the Goron Mines
The first elder
In the first room that you enter, go down the winding path to the first of the rocky platforms you need to jump across to get to the grated passageway up ahead. While jumping across you want to watch out and make sure you don't either fall into the lava or get hit by one of the erupting geysers that spring up between you and the next platform. Doing either of these will cost you a heart or two of health and you'll have to start the room all over again. When you're in the grated passageway, slash through two of the wooden barriers, then stand on the floor button near the first flame jet and put on the Iron Boots to press it down. The flame jet will be deactivated for a short while, allowing you to run across to the next floor button you'll need to press down with the Iron Boots to shut down another flame jet up ahead. With the second flame jet shut down, you'll want to take a sharp U-turn to the right and get across the wooden plank very quickly before the flame jet turns on again. Get out your shield and get ready to reflect the rocks being spat at you by a Fire Toadpoli when you're on the other side of the grating; use the Shield Attack to reflect the rock back at him to destroy him. Now climb up the ladder, open the treasure chest on top of the grating to get some rupees, then hop across a rocky platform to get to some ledges to where there's a floor button to press down with the Iron Boots to shut down another flame jet for a brief while. Along this area there are small flaming Torch Slugs that will drop down from the ceiling to attack you. Slay them quickly with the sword, then press down the floor button with the Iron Boots and quickly get over to the right of the flame jet before it turns on again. There's an iron platform next to a gate to your left where you must jump on the platform and wear your Iron Boots to weigh it down, causing the gate to be open. Slay the Torch Slugs in this area, then open the door to go into the next room.
Here there's a series of metal platforms and ramps for getting to various places in the room, plus there are these cranes hanging overhead that will serve a purpose later on in this dungeon. Take the ramp to your left and go down to a platform to slay some Bulblins and to open a treasure chest that contains a small key. Now go back up and take the ramp to your right and go up to where you must jump across some rotating platforms to get to a walkway to reach a locked door we can now open.
This door will take you into a room where you must go down a walkway to your right and slay a Dodongo that blocks your path. The strategy for dealing with them is to slash them in their tails when they're facing another direction, so target-lock onto them so you can rotate around them to do that. Then hop across some rocky platforms, watching out for the erupting geysers in your path, and slay another Dodongo before going across to an area on the other side of a covered walkway to deal with a third Dodongo. There's a chain on that side that's attached to a gate that blocks our way to a door in the covered walkway, so grab the chain and pull the gate out as far as you can go, then wait for the time to hop across platforms to get to the covered walkway and slip past the gate before it closes. This may take some tries to make it successfully past the gate, as the erupting geysers make it tricky for you to reach the gate before it closes.
In the next room there's a door on a high ledge we need to reach. First get into the water and weigh yourself down with the Iron Boots so you can slip past the iron grating before you. You only have a limited amount of time you can stay underwater in your present state, but you won't stay under for very long. Just walk right up to the floor button down at the bottom and press it. You'll be snatched up by a beam of energy and will hang on the underside of the ledge on what's called a magnetic path. Great...now your Iron Boots have turned into magnetic shoes! Just walk up onto the ledge and open the door to go into the room where you'll meet the first Goron elder in this dungeon who will give you a Key Shard. Interestingly, the Big Key of this dungeon has been split into three Key Shards that we need to collect from three Goron elders in order to enter the chamber of the dungeon boss. Open up the treasure chest behind the first elder to get the Dungeon Map. Then climb up the ladder and go across the ledge to your right to get to the other door out of this room. Before you leave, pick up the jar near the door that seems to be moving around, and you'll get Ooccoo who will help you like she did in the previous dungeon to teleport you out of there if you need to leave.
The second elder
Past the door, use the magnetic paths on either side to get to the door across from you. Watch out for the Torch Slugs that will hang along either of the two paths, because they willl knock you down from your precarious perch if they touch you. Slay them quickly with the sword. We're now back in the room with the covered walkway in it, but this time we're above the walkway. Go over to the floor button to press it with the Iron Boots, and an energy beam will snatch us up to a maze of magnetic paths we need to take to get to a door on a ledge that's flanked by two torches. Also up along these paths are Torch Slugs that we can either avoid or slay. You can also collect a Piece of Heart that's located on another ledge.
We've returned to the room with the platforms, ramps, and cranes that we've been through earlier. Go down the stairs to the platform where there are Bulblins waiting for you to be slain. Here also look out for the Fire Keese, which will burn away your Ordon Shield if it touches you while you're equipped with it (a reason that you should have gotten the Hylian Shield by now). There's a floor button on this platform to press down with the Iron Boots which will cause a crane with a magnetic surface to move around. Get over to where the crane will pass and put on the Iron Boots so you can be snatched up by the beam and move over to a platform on your right where you can drop down and go up the ramp to slay some more Bulbins guarding another floor button. Press down that button to activate another magnetic crane and ride that one to a platform on your left that's near a door. Slay the Bulblins that are on this platform before opening the door.
In the next room there's a gate across a pool of water that we need to open. First slay the Tektites that will come at you in this room. Then go into the water, put on your Iron Boots, and go over to the treasure chest on your left to get a small key. Resurface to get some air, then go over to the corner where there's an iron grate and sink down to cross through the gap in the grate so you can climb out of the water and step on the floor switch located there. This will activate an energy beam that will snatch you up onto the magnetic path directly above you. Travel along the path until you're above a ledge you can drop down onto, then press the floor button there to activate another beam that will snatch you toward a mangetic path on the opposite side wall. To get onto that path, jump off the ledge when you're directly above the beam, then in midfall whip on your Iron Boots so that you'll fall into the beam wearing them. Travel that path to the ledge where there's a crystal switch you can hit with your sword, causing the gate to be open. Jump down to where the gate is and go through it quickly before it closes. In the next room, slay the Bulblin that will charge at you, but watch out for the Beamos statues that are on top of a platform, because they will emit an energy beam from their eyes to singe you. Go to the magnetic path on your right and travel it to the left to get on a ledge which is above a gate being held up by a rope. Slash the rope with your sword to lower the gate, then drop down and go through the door behind the gate.
We're now in an open area of wooden walkways where Bulblin archers will fire flaming arrows down at us from high places. We don't have a weapon that will take them out yet, so just make your way forward on the walkways until you reach the last fork that goes to the left and right. Go up the walkway to the right and open the treasure chest that's behind a large box to get the small key. Then go back to the fork and take the walkway to the left toward the locked door we can now open. Be careful of the zigzagging ramp that's before the door.
In the next room, jump across the rotating platform, then go up the ramp to your right and you'll see a giant rotating platform we need to get across that has magnetic panels on both sides, one on one side and three on the other. I suggest you jump onto the side with the three magnetic panels on it, putting on the Iron Boots to stick onto those panels when the platform's side turns upside-down, and then quickly taking them off to cross over to the next patch when it's right-side up. If you fall off the platform into the water, you can climb up the path to take you back to the door so you can try again, but watch out for the Tektites that are down there. Once you're on the other side of the platform, climb up to reach the door and open it, which will take you to a room with the second Goron elder you'll meet who has the second Key Shard to collect. He will then tell you about a weapon wielded by "a hero of old" which a Goron guard is protecting, and that we should talk to him in order to get it. Climb up the ladder that's behind the elder and walk across the ledge to your right to reach the other door of this room, then when you reenter the room with the giant rotating platform, put on your Iron Boots and walk across the magnetic path to your right to get near the door flanked by two torches. Drop down to the ledge near the wall that the door is on and then open the door to enter the next room.
A metal gate will close down in front of the door behind you as you enter. Here there is a magnetic platform suspended by chains, and a Goron guard wearing fearsome armor named Dangoro who will tell you that this is a forbidden place, and he will protect the treasure from the likes of you. He will jump onto the platform, causing it to fall onto the lava below with you on it.
Make sure you have your Iron Boots on throughout the entire fight, because Dangoro will cause the platform to tilt this way and that to make you fall off it into the lava. Get as close as you can to him and wait for him to raise one or both arms to strike you down, then strike his belly with the sword. This will cause him to curl up into a ball so he can roll over you. Stand your ground and hold down the A button when he's close to you so that you can grab onto him and throw him over your shoulder. What you want to do is throw him into the lava lake three times. After the third time in the lava lake, Dangoro will realize what your purpose is in the mines and allow you to cross over into the next room behind him so you can grab the weapon of "the hero of the past". The lava will then rise, bringing the platform back up to where the two doors of the room are located. The metal gates in front of both doors will be raised, and Link can proceed onward to the next room.
The third elder
Go across the stone bridge to the platform in front of you where you'll see a treasure chest that contains your next useful item -- the Hero's Bow. You will get 30 arrows to start off with, but there is a place called Purlo's STAR Game you can go to and play so you can increase the maximum amount that you can carry. Use the Bow to shoot at the rope holding up the gate before you in order to lower it so you can cross over into the next room where there's six inactive Beamoses surrounding you, each blocking six small chambers. Slay the Torch Slug that will drop right down in front of you, then continue to go forward to where there's a single Beamos blocking your path. When you get close to it, this will activate that one and all the other Beamoses in the room. Shoot at the eyes of each of them from a safe distance, then pull out the Beamos that's blocking the chamber at center right from the entrance so you can get to the door behind it. You'll now enter the room with the third Goron elder in it who will give you the last Key Shard, completing the formation of the Big Key. He will tell us that with that key, we can go into the room where Darbus is being held and help him. Now leave that room the same way you came and pull out the Beamos that's blocking your path to the south of the room so you can get to the door behind it.
The boss chamber
In the next room, run toward the iron grate ahead of you, slaying the Fire Keese that will get in your path, and do a roll attack into the grate to knock it down. Now proceed toward the stone platforms that we will have to hop across, but be careful of both the Torch Slugs hanging on the ceilings over some of them and a couple of Dodongos roaming around on one of them. You can use the arrows to take them out before you cross over the platforms. There's a gate we need to open, so go over to the floor button that's to the right of the gate to activate a beam for pulling yourself onto the ceiling with the Iron Boots on and head for the alcove above the gate where there's a crystal switch we can shoot at. Slay the Dodongo that's clinging to the ceiling here with your arrows. Drop down in front of the gate when it opens and go through the door into the room with the platforms, ramps, and cranes that we've been through earlier. From here we're going to be trekking through some rooms again in order to get to the area with the Bulblin archers, where we can now take them out with the Bow. Go over to the place on the right where you got the small key and shut down the Beamos with an arrow before pulling it out, causing a door to a ramp to be open. Go through there and you'll be on a higher level where you can take out two more Bulblin archers; you can hit the explosive barrel they're standing near to dispose of both of them at the same time. Get rid of the explosive barrels blocking your path to a floor button you need to press to activate another magnetic crane. Drop down to the platform where the magnetic crane will pick you up with the Iron Boots on and aim for the ropes holding up a gate to lower it when the crane moves near it. Drop down onto the gate and go through the door into the next room.
Here there are Bulblin archers guarding another gate held up by a rope at the bottom of a metal passageway. You want to take most of them out first before you go down there to cut the rope and lower the gate, but watch out for their arrows while you do it. When the gate is lowered, a pack of Bulblins will come charging at you, which you can dispose of with the sword. Beyond that is the Big Key Door that leads into the boss chamber. Smash whatever jars you can find here to get hearts and a fairy before you open the door and face the dungeon boss.
Goron Mines Boss: Fyrus
In the next room, Link sees a giant Goron wearing a helmet with a crystal over his head, held by giant chains and slumbering. Then the crystal glows, and the Goron awakens with a fierce growl, breaking himself free of the chains and igniting himself on fire. This is the dungeon boss Fyrus, referred to also as Twilit Igniter. His main form of attack is to whip his arm chains at you if you are close enough to him. He can also breathe out fire, and he will create an explosive ring of fire to hit you from a distance.
What you want to do is get enough distance between you and Fyrus so you can aim an arrow at the crystal on his forehead. This will make him stagger around in pain. While he's doing this, quickly get behind him, grab a hold of one of his leg chains, whip on your Iron Boots, and move backward so that he will be tripped up and fall down, putting out the flames from his body. Then let go of the chain, whip off the Iron Boots, and go over to his forehead to strike at his crystal. Fyrus will then get up and ignite himself again with the crystal glowing. Put some distance between yourself and him so you can repeat the same strategy two times. With enough hits, Fyrus will writhe in agony before its body hardens and the crystal drops from his helmet, which will turn into a Heart Container. Fyrus' body will then explode into Twilight bits which will form into another Fused Shadow that Midna will collect. With the Twilight bits gone, Darbus will be restored to normal and not even remember what has happened to him.
You have completed the Goron Mines. Collect your Heart Container, and enter the portal to leave the dungeon. You will be asked to save your game at this point.