i raised the water levels so that i can now access the boss but i dont have any idea of how to get the key to the boss room, also from where do i get the master sword?
I can't tell you exactly where you get the boss key and how to get there, but just look on your map and look where you havn't gone yet. Thats all i can help you with this, sorry bud.
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You get the Master Sword once you visit the Sacred Grove, which is almost right after the water temple
