Get the Razor Sword!:
1st you must follow Darmani's ghost (use the Lens of truth to see him) to his grave. Play the Song of Healing, get his mask and use it.
Pull back his gravestone and Ta-daaaaa! There will be a hot spring. Quickly bottle some water (I'd switch to Deku for the next part) and run. Go to the frozen lake and dump it on the lake to uncover the 2nd hot spring.
Bottle that and run into the Blacksmith's place and empty it on their fire. And the guy will show his thankfulness by severely over-charging you for 100 rupees and a cruddy sword.
It's not even close to worth it. It breaks after 10' hits and can't be taken back in time with you.
Get the Guilded Sword!:
Get the Razor Sword and go to the Goron Racetrack. Win, and get some Gold Dust. Take it to the Blacksmith dude-person and give it to him and Ta-daaaaaa again! You've got a really great sword.
It never breaks and can be taken in time with you. Isn't that just fandy dandy? =)
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