Go forward through the tunnel. Ignore the enemies (you can only attack them if you have the iron boots on; you can't swim and fight at the same time) and end up in front of a door. Behind the hole you swam in from are 10 water bombs and 20 arrows in chests. Go up the stairs and jump onto the pull lever. When you grab on, the gate opens. Go in. In the next room, hit certain stalactites (the ones with thin bases holding heavy rocks underneath) with bomb arrows to knock them down and make a path.

Advance; to the left of the door out is a chest with 10 more water bombs (you have to have knocked down the stalactite near it to be able to climb up). Go through the door. There's a lizardman on the other side of the bridge. The secret moves are good against these guys, namely shield bashing, back slicing, and the ending blow. Go through the door into the great hall. Go down the stairs. Circle all the way to the right for a chest with 20 arrows. Near it is an empty gap with a pull chain thing. Jump on it and grab it. Go up the stairs; to the left is where I found Ooccoo. To the right of the stairs is a door. There's a waterwheel blocking the way when you go through it, so you can't go past yet (the same is true for the level below it). Grab the pull-chain in front of that door and go down the stairs to go on. Now you should be in a room with three suspended things hanging in the center. Go to the right, down the ramp. Shoot the stalactite over the bubbling geyser to plug it up and walk over it. Climb on the seaweed over to the other side.

Jump on the platform. There's a sporadic geyser in front of you. Shoot the stalactite above it with a bomb arrow, then jump across when the geyser is activated to use the stalactite as a stepping stone. You get the small key. Head back to the center room. Go up the stairs and around to the right so that you are back on the west side again but one floor higher. Unlock the door and go in. After the bridge, you will be in a big room with walls and grates. To the left of the door is a chest with 5 water bombs in it. To the right are two stalactites. Shoot them both down with bomb arrows, then jump on the one near the seaweed and climb up and on top of the wall. From the wall, jump to the pull ring and you will open the gate. Take the door to the left. Jump across the giant gear and kill the lizardman. Go through the other door. Turn to the left when you come out for a small key. Go back through the gear room and take a left when you come out the door you went through before (in the hallway, not in the gear room). Blow up the rocks with a bomb. Go through the door.

When the green thing jumps into the bubble, blast the bubble with a bomb arrow and kill the green thing before it makes another one. Unlock the door on the left. Turn to the right and jump onto the algae on the wall of the pit. Climb up and begin walking up the spiral ramp/waterway. At the top is a chest with ten water bombs. Climb up the arch and jump onto the pull ring to start the water flow. You can see a chest, but you can't get that until later and it's going to be very annoying to do so. Jump into the water flow and get swept down the slide. When you reach the bottom, go to the previously unreachable center island and pull the pull-ring. Follow the stream of water and go through the water wheel when it turns enough to let you through. In the pot near the grate there is a fairy. Put it in one of your bottles for later. Go back through the wheel and into the gear room. The gear is moving now, affecting the room below you. Jump down into the lower room. Climb to the entrance to that room and stand on the rock outcropping. Jump onto one of the hanging platforms. The first room you will go to is in the north. Once in this room, go left for a small key. Leave the room and jump on another hanging platform. Ride this one to the western outcropping and jump on it.

Go through the door and use the key on the door ahead of you. Go into the water and go to the end. Put on your iron boots and drop a bomb on the rock. Go forward. When the tunnel heads upwards, de-equip your boots and swim to the surface. The hatch closes behind you. Some enemies drop down; kill them and look up. This is our sub-boss fight. This giant frog thing will shake its eggs off and the spawn will come attack you. Kill them all (spin attacks and quick slashes work best) and it'll go back up to the ceiling. Roll out of the way before it drops onto you (you can see its shadow). Attack its tongue. Repeat until it dies. The third time should give you the "finish" option. Open the chest to get the clawshot.

Zelda Twilight Princess Walkthrough