This part will take you through the entire Temple of Fire.
Inside the Temple
As we enter the temple, there will be walls of fire that we will have to weave our way around to reach the first room, where there's a rotating wall of fire near its center. Head to the room on the right, then go up, jump across the platform where the locked door is, then look at the map hanging on the wall that will show us a path through one of the rooms we will go through. Note where that room is on your map of this floor and copy the path onto it. Then go south into a room where the door will close behind you, forcing you to fight a bunch of Keese flying around. Destroy them all, and the door will reopen and a wall of fire blocking your way to a treasure chest in a nearby room will go away. Open the treasure chest, and you'll get the small key. Go back into the room where we found the map, leap onto the platform where the locked door is, and open it. Now go through the door into the next room where we follow the path that we marked out from the map, avoiding the trap doors along the way, and hit all four switch orbs at the same time at the point where the path ends. A door on the north wall of the center room will open. Head back into the center room and go through that door up the stairs to Floor 2.
In the first room that we enter, go around the square divider, slaying the Red Chuchu and avoiding the Electric Chuchu, and hit the switch orb in the upper left corner. This will cause the red blocks to go down and the blue blocks to go up. Then run around the path at the east end of the room and go through the door at the south wall that will close behind you into a room where you must slay Zols and Gels to reopen the door and cause a treasure chest to appear. This will give us the Boomerang, which will be very useful in this Temple. Now head over toward the east end of the room, where we see a switch orb on the north platform, and direct the Boomerang to hit it. This will make the wall of fire blocking our path to the west to disappear.
Now go along the path that will take us to the room on the northwest part of the floor, and quickly direct the Boomerang to hit both switch orbs on the other side of a fiery chasm. This will cause the wall of fire blocking our path to the stairs to disappear. Now go down the stairs and back to Floor 1.
In the room that we entered, hit the Electric Chuchu with the Boomerang to stun it, then slay it with the sword. Now direct the Boomerang to fly around in a U pattern to hit the switch orb on the other side of the wall. This will cause the red blocks to go up and the blue blocks to go down. Now go down the stairs into the room on the south, take care of the Electric Chuchu in it, then make the Boomerang fly in a U pattern toward another switch orb that we otherwise cannot reach. This will cause a wall of fire blocking a door to the right to disappear. Now go south into a room where the door will close behind you, and two Fire Bubbles will float around in the room to burn you. Hit each of them with the Boomerang to stun it, then slay it with the sword. The closed door will reopen, and a door to the left side of the room will open. Go through that door and up the stairs back to Floor 2.
In the room that we enter, avoid the two spinning walls of fire as we leap across platforms to reach the right side of the room, slay the Fire Keese, and then go down and pull the switch. Now go back across the platforms, slay another Fire Keese, and go down and pull the other switch that you see. This will cause a door on the north wall to open. Go near to the room where the door leads into, and here use the Boomerang to time a hit with a rat that scurries back and forth between holes with a small key. Grab the key, then leap across the platforms again and head into the room on the right. Hit the switch orb with the Boomerang to make the red blocks go down, then slay the Octorok waiting between the red and blue blocks, then direct the Boomerang to hit the switch orb again to make the blue blocks go down. Go across to the other side where the locked door is and use the key to open it, then go through it and up into Floor 3.
In the room that we entered, slay the Zols and Gels, then blow out the two candles flanking the door blocked by the wall of fire on the north end. The wall of fire will disappear, allowing us to go into the next room where there are four switch orbs in each corner of the room that we need to hit in order. But first we need to go south past a rotating wall of fire where we see a wall map directing us which order we need to hit the orbs in. Copy the order onto your map, then go into that room and direct the Boomerang to hit them in that order. (The order is southwest, northeast, northwest, southeast.) This will cause a small key to fall onto a platform that we can retrieve with the Boomerang.
Now go back into the room that we first entered toward a locked door in the lower left corner of the room and open it. Then as you head toward the left through the hallway, Ciela will point out a nearby door that we need a Big Key for. Head to the left and enter a room where the door closes behind you, and you'll have to fight off Electric Chuchus and Fire Keese while avoiding flames being thrown from a torch to reopen it. This will also cause a door on the north wall to open. Go through that door, then go left, then up, then right to slay two Fire Bubbles that will cause some walls of fire to disappear. Go through the north door into a room where there's three torches sitting on platforms, the left of which is the only one that's lit. We need to light the other two torches in a single throw of the Boomerang, so direct the Boomerang to hit the left torch, then the north torch, then the right torch. This will cause a wall of fire blocking our way to the room with the Big Key to disappear.
Now head back down, right, and then down to a gap on our right, then direct the Boomerang to hit a switch orb in the upper left corner of the next room on the right. The gap will close itself up, and we can enter the room, watching out for three spinning walls of fire in the center, then go north and up the stairs to open the treasure chest that contains the Big Key. Now our traveling will be slower when we carry the Big Key, so when we get to the three spinning walls of fire, toss it ahead of you, then pick it up when you're in the clear. Carry the key back through the rooms to the door that we saw earlier and throw it into the lock. The door will open, and we can climb the stairs to Floor 4.
There's nothing that we really need to get on this floor, just pots we can break for hearts if we need them, and a blue portal that will take us back to the entrance of the Temple. Proceed north and up the stairs to meet the boss of the Temple.
Temple Boss: Blaaz
The boss we'll be fighting is Blaaz, who generally likes to split up into three smaller beings in order to attack us. Use the Boomerang to fuse all three of them back together, then strike Blaaz repeatedly with the sword once he's together. He will then vanish and reappear elsewhere, causing fiery rocks to fall down from the sky and attack us. Just simply avoid them. Eventually he will try splitting himself up again. Use the Boomerang to fuse his smaller selves back together and attack him when he's together. After several successful strikes, Blaaz will freeze up as his body turns to sand and explodes before it disappears. Then Link will see the same seal he saw on the map appear on the floor, and a red fairy will appear. This is Leaf, the Spirit of Power who serves the Ocean King whom we have freed. We now have two fairies to accompany us, and a treasure chest will appear that will give us a Heart Container to extend Link's heart meter.
You have completed the Temple of Fire! Now step into the blue portal and return to the entrance of the Temple.