Sahasrahla says to find one of the Pendants in the Tower of Hera, which is in the northern mountains.
Tower of Hera 1F
Hit the smiling barriers with your hammer. The smiling barriers are called moles. They pop up after a while. If you stand on them when they pop up, they throw you into the air in the direction that they are angled toward. Hit the blue switch to the north.
There are some turtles in this area that you can only damage if you hit them with the hammer, then with your sword. Hit a red switch to reach the upper area. Pound the moles in the northwest area, then stand on them to be sent up to the ledge in the northwest. Merge with the wall and go through the barred window to get a purple rupee. Go back into the room.
On the northwest ledge, merge with the wall and go south to the next ledge. Go to where the blade traps are going back and forth. Merge with the wall there to go across. Go north and pound the moles, then stand on them to be popped up to the upper ledge. Pound the huge mole to be sent up to the next floor.
Tower of Hera 2F
Be careful of the hardhat beetles that wander around up here. They knock you back if you hit them, which might cause you to fall down below. You can knock them off of the edges to get rid of them, or just hit them twice with your sword.
Fall into the center hole to reach the chest, which contains the compass. Use the huge mole to be sent back up.
Use the huge mole to the left to go up to the next floor.
Tower of Hera 3F
Merge with a colorful wall to reach one of the blue switches. Hit it and go to the red switch on the right and hit that. Then hit the blue switch to the right. Go up the stairs and merge with the wall near the door. Go to where the red wall is and walk across it to reach the key.
Unlock the east door and go through.
You're now outside. Step on a moving platform when it passes by. Be careful of attacking birds. When a wall blocks your way, merge with it and go around to the other side to get back onto the moving platform. Then when there is a wall to the right, merge with it, then merge with the cube-shaped moving platform when it comes down to your level. When it rises again, go around to where the door is.
Tower of Hera 4F
Go inside. Go to the north part of the room and hit the crystal switch. Use the hammer to hit the huge mole, then stand on it to be sent up to the next floor.
Tower of Hera 5F
Hit the crystal switch. Stand on a spot where the wall was before you hit the switch, then hit it again so you rise up on the wall. Drop down to the chest. It contains a blue rupee. Now stand on a lowered wall and hit a crystal switch to go up. Merge with the wall and go through the window that has bars on it.
Step onto a moving platform when it goes past. Be careful of the blade traps that get in your way. When a wall comes out and blocks you, merge with it and go around so you can pop out onto the moving platform when it's under you again. Soon you'll need to merge with a wall when your moving platform goes under it. You can go into a little alcove to get a recovery heart. Now wait for the cube-shaped moving platform to come to the bottom. As a painting, merge with it. It takes a long time to go back up, so be careful. Let it take you to the next floor. Go into the door there.
Tower of Hera 6F
Some red stalfos attack you. These will throw a bone at you if you hit them, so be careful. You can kill them instantly with the hammer, but keep in mind that the hammer doesn't swing right away, so make sure the stalfos are not too close to you before using the hammer.
After the battle, a green portal appears, so you can warp out and save if you wish. Back in the green portal room on 6F, step on the rising platform to be raised to the next floor.
Tower of Hera 7F
Be careful of the turtle and the hardhat beetle. Hit one of the crystal switches. Now use the hammer to break the cracked floor in the northwest and northeast of the room. Drop down to the right to get monster guts, then use the smiling thing to go back up to the upper floor. Drop down to the left to get a key. Get back up by using the mole. Use the key on the locked door on the left.
Stand on the platform with the smiling thing. Hit it with the hammer when it moves south. Stand on it to be send up to the ledge up above.
Tower of Hera 8F
To get a silver rupee, merge with the wall and go east until you reach the area just before where the wall turns at an angle. Pop out of the wall there to fall below to a ledge on 7F with a chest that contains a silver rupee. Merge with the wall to get back to the moving platform with the mole on it. Use it again to jump up to the next floor.
Tower of Hera 9F
Get on the next moving platform. Hit the mole when it is about to go under the left or right side of the square up above. If you time it correctly, you will be sent up to the door. Go through.
Up above, the tiles will fly at you. Hold up your shield to avoid getting hurt. After all of the tiles are gone, a moving platform will start going up and down. There is a secret fairy fountain below the moving platform. Drop down there to find a chest that contains a purple rupee. Step on the warp tile on the top right to go back up above.
Stand on the moving platform to go to the next floor.
Tower of Hera 10F
There are four crystal switches around this area. There is one to the north, one to the west, one to the east, and one to the south. Hit all four to make the platform in the top right corner come down. Hit the mole on that platform to go up to the next floor.
Tower of Hera 11F
Use the mole on the right to go up to the big chest, which contains the big key. Then Drop back down and use the mole on the right to go to the boss door. Or you can just merge with the wall next to the big chest to reach the big door.
Use the moles outside to reach the next floor.
Tower of Hera 12F
If you're ready to fight the boss, use one of the moles in the corners to reach the boss's floor. Don't collect the recovery hearts on 12F because you might get knocked down to this level and might need the hearts.
Hit the red spot on the giant moldorm's tail to hurt it. It will spin around for a moment then start moving again. Watch its eyes so you can avoid letting it run toward you. After you hit it a few times, it will turn red and start moving more quickly. Carefully hit its vulnerable spot while avoiding getting hit.
After the battle, pick up the heart container, then the Pendant of Power.