Well, it’s a large fetch quest: Once you’re an adult, go to the Cuccoo lady in Kakariko village. She will give you a Pocket Cuccoo egg. Once it hatches, wake up Talon in a house in the same village. Then, show the Pocket Cuccoo to the lady, she will then entrust you with Cojiro, a blue Cuccoo that you must bring to the guy who thinks everything is disgusting in the Lost Woods. After showing him Cojiro, he will give you a. Odd Mushroom. You have a certain time limit to bring this to the old lady behind the Potion Shop in Kakariko Village. Remember that teleporting ANYWHERE will make the timer immediately go to one second remaining, so that’s not an option. Once you do, she will give you an Odd Potion (or Odd Poultice in the N64 version, I play on 3DS). Bring it back to the guy who gave you the Mushroom, but once there, you’ll se that Fado the Kokiri has taken his place! She will want the Potion back, in exchange, she’ll give you a Saw. Bring this to the leader of the Carpenters in Gerudo Valley. You’ll need either Epona, or the Longshot to cross the bridge if it’s not repaired yet. He’ll give you the. Broken Biggoron tool, so go bring that to Biggoron on the summit of Death Valley. He’ll be blinded, so he asks you to bring a Prescription to King Zora (who has to be unfrozen), but he’s run out of Tear Drops, so he gives you instead an Eyeball Frog to bring to the old lady in the Lake Hylia laboratory, again, with a time limit. She’ll make Tear Drops and give it to you to bring to Biggoron, along with another time limit. Once you bring it to him, you can relax, because now everything’s chill. Biggoron will give you a claim check to give it to him while he makes the Biggoron’s Sword for three days (use the Sun’s Song to skip this). After three days, show him the Claim Check, and the Biggoron Sword is yours!