The Biggoron Sword
TRADE SEQUENCE FOR THE BIGGORON SWORD
1. Get an egg from the girl who raises cucco's. When the egg hatches, go to the house where Talon is sleeping and wake him up. Go back to the cucco girl and give her back the cucco and she'll give you a blue cucco, Cojiro.
2. Bring Cojiro to a guy sitting at the stump of a tree in the Lost Woods. Give him Cojiro and he'll give you the Odd Mushroom.
3. Bring the Odd Mushroom to the witch living in the house behind the potion shop. She'll then give you the Odd Potion.
4. Bring the Odd Potion back to the Lost Woods and give it to the Kokiri girl that is standing where that guy was sitting at the stump. The Kokiri girl will give you the Poacher's Saw.
5. Bring the saw to the head carpenter at Gerudo Valley. In return, he'll give you a broken Goron's Sword.
6. Bring the broken Goron's Sword to Biggoron at the top of Death Mountain. He'll give you a prescription for eyedrops.
7. Bring the prescription to King Zora. Zora will give you the Eyeball Frog.
8. Bring the Eyeball Frog to the scientist at the lab at Lake Hylia. In return for the Frog, he'll give you the eyedrops.
9. Bring the Eyedrops back to Biggoron and he'll give you a claim check for the Biggoron sword.
10. Continue to play the sun song until three days go by in the game. Biggoron will then give you the Biggoron Sword which is twice as powerful as the Master Sword