This awesome sword is the strongest blade in the game, but it is also quite a task to acquire. Basically you have to take items to a bunch of people. Some items have time limits so don't warp or else it will reduce time and you need Epona for this. Use the same carrot method when you beat Ingo for this. The following is the order of each person that you will have to take/collect an item to/from:
1. Pocket Egg-Cucco Girl (Kakariko Village) (Note: Make him happy by waking up Talon and then go back to Cucco Girl) 2.Corjiro-Brother of Cucco Girl (Lost Woods) 3.Odd Mushroom-Mother behind potion shop (Kakariko Village) 4.Odd Potion-Kokiri Girl (Lost Woods) 5.Poacher's Saw-Carpender (Gerudo Valley) 6.Goron's Sword-Biggoron (Death Mountain) 7.Prescription-King Zora (Zora's Domain) 8.Eyeball Frog-Professor (Lake Hylia) 9.Eye Drops-Biggoron (Death Mountain)
You will receive a claim check after step 9, which you should give to the big Goron on Death Mountain. Play the Sun's Song 6 times or wait three days to get the Biggoron Sword.