Dangoro

The Dangoro is a giant goron who will not let you pass into the next room. He will start by bringing down the magnetic platform down into the lava. The next thing he will do is come after you slowly. Equip your Iron Boots and your sword so you can be ready. Once he starts to swing in for a punch, slash at his belly until he falls down. Right after he does this, he will roll up into a ball and roll straight at you. Make sure you're near an edge then hold down A to stop him from killing you and also to throw him into the lava. Throw him into the lava two more times and he will be defeated and you can recieve the Hero's Bow.