Barinade
Bio-Electric Anemone: Barinade is the third boss in Ocarina of Time, residing in Jabu-Jabu's Belly. He is the guardian of the third Spiritual Stone, Zora's Sapphire.
At the start of the battle, Barinade is attached to the ceiling of the arena, sucking life energy from Lord Jabu Jabu. He must be seperated from the deity, and this is done by using the boomerang on the three tentacles that attach Barinade to the ceiling. But watch out for Barinade's ability to shoot lightning from it's other three tentacles.
Once seperated, Barinade is surrounded by a group of electrified jellyfish, preventing any attack on its soft body. Getting rid of them should be the player's second task. This can be done with the boomerang, while Barinade sends them out to attack Link.
Once all of the jellyfish are gone, Barinade will start to spin wildly through the room, whilst firing blasts of electricity at Link. There are more jellyfish that protect him while he is spinning. Take them out with the boomerang like before to get a clear hit on Barinade's body. Use the boomerang to stun him. From there, attack using the Kokiri Sword. After several strikes, Barinade falls. (And blows up in a rather grotesque manner.)
After getting rid of this foe, you will be rewarded with a Heart Container and the third Spiritual Stone, Zora's Sapphire. (As well as a very angry and huffy Princess Ruto.)