After going to Tarm Ruins and making your way through the Lost Woods, you reach the Ancient Ruins.
Go north twice from the entrance. There is a rotating device here. Get into it and go east twice.
Get past the blade traps and cut the crystals with your sword. There is a chest on the right side of the room that contains five rupees. Exit south.
Go to the south wall of this room and bomb the wall at the spot straight across from the northern entrance. Go inside to get a bunch of rupees.
Get a Key
Go north from the rupee room and west twice. Exit north to reach the rotating device again. Get in and exit west.
Go north. Use Pegasus Seeds to jump to the area in the top-left of the room. Use the Magnetic Gloves to push the N magnet to the bottom-middle of the room. Jump back over the gap and push the N magnet across the big gap on the right side of the room and slide it to the top-right corner, then pull it toward you onto the switch. Get the key that falls.
Get the Dungeon Map
Go south twice. Go to the stairs in the bottom-left of the room and exit north to get the Dungeon Map.
Get a Second Key
Go south from the dungeon map and then use the northeast exit. Go east. Use the rotating device and exit south.
Unlock the key block, then use the Magnetic Gloves to pull the N magnet onto the switch. Go through the west door.
Go north, then east, and use the rotating device. Exit north.
Use the Magnetic Gloves to put the N magnet on the switch. Go up the stairs that appear in the northwest corner.
Quickly go over the spikes, then make your way through the spinning blade trap area on the right side of the room. Exit south. Open the chest to get a key.
Get the Compass
Go back the way you came and use the rotating device. Go west, south, east, and north and use the rotating device again. Repeat this until you can exit east from the rotating device.
Unlock the north door and go through.
Use the moving platforms to reach the chest in the northwest corner. Open it to get the Compass.
Exit east from the room where you got the compass. Do yourself a favor and kill all of the keese in the room, then go to the east side of the room and go up to the switch. Step on it to extend a bridge. This also makes the floor collapse, so use a pegasus seed, then go around to the bridge and cross it and exit west. Go up the stairs.
Open the chest to get bombs.
In the room where you got bombs, use a bomb on the cracked wall in the bottom-right corner of the room. Exit south.
Open the chest in the center of the room to get rupees.
Get the Magical Boomerang
Go to the left side of the room and go down. Exit west. Jump over the gap and push the trampoline onto the grey tile. Jump onto the trampoline.
Go south, then east. Go to the right side of the room and open the chest to get the Magical Boomerang. If you throw the boomerang and hold the throwing button, you can use the directional pad to change the path of the boomerang. It comes back to you eventually. Taking the boomerang makes all of the armos statues come to life, but they are vulnerable to the magical boomerang, so hit them twice to kill them, and exit west.
Go to the bottom-left corner of the room and cut the crystals and fall into the hole. You will end up in the room north of the entrance. Exit west.
Go to the left side of the room and go up the stairs, then exit north, then west. Go to the top-right corner of the room and open the chest to get rupees.
Make your way through the blade trap area on the left side of the room to step on the switch in the bottom-left corner. Then go back to the north part of the room and exit north.
Use the Magical Boomerang to hit the crystal switch and make stairs appear in the north wall. Go up.
Exit south, then use the Magical Boomerang to hit the crystal switch and open the south door. Avoid the spears that shoot from the north wall and go to the door that opened. Exit south.
Go to the top-left corner of the room and drop down the hole. Exit south, then northeast. Use the slingshot to shoot ember seeds at the torches, making stairs appear in the north wall. Go up.
Exit east and take the rupees. The statues disappear and the walls start to squeeze together, so use a pegasus seed and exit east.
Get the Boss Key
Keep making your way around, using pegasus seeds and the Roc's Feather to make it around the path before the wall squeeze shut. At the end of the path you find a chest that contains the boss key.
Get a Third Key
Exit east from where you got the boss key and go down. Use the stairs there.
Kill all of the shrouded stalfos and then push the top-left block to open the door. Exit north.
Go to the northeast corner of the room and fall down the hole. Go along the ledge to reach the south part of the room and open the chest to get a key.
Reach the Mini-Boss
Go back up the ledge and use the trampoline to go back to the previous room. Go to the northwest corner of the room and unlock the door. Exit north.
Vire is very easy. He will fly toward you. Just hit him with your sword when he's close. Eventually he will fly slowly around the room spitting fireballs at you, and sometimes will spit a fireball that follows you. Just hit the fireballs with your sword to get rid of them, and hit Vire when he gets close. After you hit him a few more times, he splits into two bats that stay near the ceiling and sometimes fly down at you. Hit them with your sword. After you get rid of both of the bats, Vire gives up and flies away, ending the battle.
Reach the Dungeon Boss
Exit east from Vire's room. Get past the spears, blade traps, and cannons to exit east. Jump over the rollers and go to the northeast corner of the room and press the switch, then go to the south wall and exit south.
The two switches in here are random. Step on a switch and it will either make Ropes fall from the ceiling or make stairs appear in the bottom-right of the room. Keep trying the switches until the stairs appear. Use the stairs.
Go to the north of the room and exit north. Use the Magnetic Gloves to push the N magnet into the Hardhat Beetles. The N magnet kills them. Exit west.
Go to the left side of the room and use the Magical Boomerang to turn all crystal switches to red. This opens the door. Go to the southeast of the room and exit south.
Push the trampoline all the way south, then push it to the right four times. Jump onto it and use the Magical Boomerang to hit the crystal switch. Drop down the hole, then go to the left side of the room and go up the stairs. There is a block directly to your right. Push it to the right, then go up to the boss door. Unlock it and go through.
The red plants are vulnerable to the Magical Boomerang when they open their mouths, so hit them then. Manhandla will move more quickly each time you kill a red mouth. After all the mouths are gone, hit the green plant with the Magical Boomerang until it splits apart, revealing a jewel inside. Hit the jewel with your sword.
Get the Essence
Stairs appear in the north wall. Go up. Walk up to the altar to get the Blowing Wind. Outside, the Maku Tree mentions a Graveyard west of Horon Village, but to get there you have to find a way across the sea.