4:40 The hardest enemy in the whole game. I consider this event alone as a boss battle.
Assuming you're coming back from the direction of the Ice Cavern, the Zora
king will be right here in front of you encased in red ice. Use the Blue Fire
to free him and then speak to the king. As a way of saying thank you, he will
give you the ZORA TUNIC which allows you to breathe underwater. With this in
hand it's time to leave and return to the Hyrule Field. Play Epona's Song to
summon the horse and then make your way to Lon Lon Ranch but don't go inside.
Instead ride the horse northwest of the ranch and step beside the lone yellow
tree. When you get off you should feel your controller rumbling when you
stand beside the tree. Place a bomb there at the base and it will blast a
hole in the ground. Down here is a small body of water, what you need to do
is swim into it and equip the Iron Boots. You will sink down to the bottom
and acquire a PIECE OF HEART . Leave this area and head for Lake Hylia.
When you arrive there, make your way over to the laboratory thing beside the
bridge and step on the Magic Bean plant. When it rises up, jump off
immediately onto the roof of the house and climb the ladder. Before climbing
the ladder be sure to equip the Fairy Bow and aim up, eliminate all birds
which might potentially knock you off the ladder. At the top here you will
find PIECE OF HEART . Jump down and get on the Magic Bean platform once
again, this time stay on it and it will bring you over to the Fishing Pond.
Fishing as Adult Link is quite similar to fishing as Young Link, the one main
difference is that the fish are bigger. Your goal is to catch the fish in the
very middle of the pond, the enormous one swimming around the broken logs and
stuff, it's pretty much always in the same place. This fish takes forever to
actually bite your hook, I must have cast at least two dozen times or more.
It eventually did bite, sometime during the daylight hours. This fish should
be at least fifteen pounds or more, which will net you the reward GOLDEN SCALE
and allow you to dive underwater for nine seconds as opposed to six.
Now that you have this, leave the Fishing Pond and head for the laboratory
again, but this time actually go inside. There is a creepy old man in here
beside the small pond. Equip the Iron Boots and jump into the water, have
your Hookshot equipped as well. At the very bottom, roll into the crate down
here and a GOLD SKULLTULA  will pop out, you can kill it using the
Hookshot. Note the three Red Rupees down here, feel free to collect them as
well. Now swim to the very bottom of this pond using your new Gold Scale, not
you Iron Boots and speak to the man to acquire PIECE OF HEART .
The Water Temple is located in the middle of Lake Hylia, on the north side of
the centre island but underwater. You need to equip the Iron Boots and the
Hookshot and then jump down to the gate. Fire the Hookshot up at the blue
diamond above the gate and it will open, allow you to enter the Water Temple.