You will notice that you cannot actually reach Dongorongo at first because of the quicksand in the way. However, our good friend Gongoron appears on the top of the screen and wants to bring down the beast together. Switching between Gongoron and Link is the same as before, just tap the button that appears. As you are battling with Dongorongo at the top, Eye Slugs will periodically attack Link at the bottom. Quickly switch on over and defeat the eye slugs.
When controlling Gongoron, watch out for the bosses two main attacks. One is simply dashing into the little Goron and the other is shooting three balls of fire out of its mouth. Avoid his attacks and try and hit Dongorongo from his side. Hitting him from the front will do nothing because of his massive armor. However, he becomes stunned for a split second. Once you get a chance, target its side and do a jump attack to weaken Dongorongo. Jump on him several times until he is stunned on the floor. Then quickly switch back over to Link and trace a Bombchu right at the monsters mouth for a huge blow. Switch back and forth between Gongoron and Link and repeat this process until you've nailed Dongorongo with three bombchus.
Once you do so, it will fall to the floor and a door will open up at the top of the room. Gongoron heads through the door saying that the Pure Metal lies behind it. A bridge appears near Link so he can reach the door as well. Cross the bridge and make your way to the door, but wait! Dongorongo isn't finished yet!
The beast stands back up, the bridge disappears, and the door shuts, trapping Link in this enclosed area with the monster. A blue orb will stick out of Dongorongo, revealing a weak spot. He is more furious then ever now and will shoot endless fire out of his mouth as he spins around the room. He also walks more aggressively and the eye slugs around appear more frequently. Dongorongo will get on its hind legs and try to suck Link towards him. This is your chance, pull out your Bombs and toss them into Dongorongo's mouth. They will explode and it will fall on to its side. Run on over and slash at its blue circle on its back over and over. Repeat this process several times until the monster has been defeated
The player is rewarded with a Heart Container as well as the pure metal Crimsonine.