Instructions
Equip your boomerang. As with all boss fights in every "Zelda" game, you need the item you acquired in that boss's temple to win. You will have come across the boomerang earlier in the dungeon, and it is the only weapon with which you can effectively beat Fraaz.
Attack Fraaz with alternating elements. The room will have both a red torch of regular fire and a blue one of ice flames. When Fraaz is red, use your stylus to draw a boomerang path that goes through the blue flames, and then target Fraaz. When he is blue, target him with the red flames. If you do this correctly, he will be stunned. While he is stunned, run up and slash at him with your sword as many times as you can.
Watch your upper screen when Fraaz splits into two smaller monsters; he will split into them after you attack him while he is stunned, and they will be represented in your upper screen by a red and blue icon.
Target the two smaller monsters with alternating elements. Attack the blue mini-Fraaz with red flames first and slash at him while he is stunned. Quickly attack the red mini-Fraaz with blue flames before he can revive his partner. When both are down, the giant Fraaz will re-form and destroy the torches.
Dodge Fraaz's attacks of fire and ice and use them against him. Fraaz will breathe fire first, which will burn on the floor for a few seconds while he switches to his ice form. When he switches, aim your boomerang through the fire and target him. If he is inhaling for another attack, you will have to hit him twice to stun him. Slash him with the sword again. Fraaz will split into two.
Attack the new mini-Fraazs with their partners' attacks. You won't have any torches to work with, so you will have to watch your upper screen to tell which Fraaz is fire and which is ice. Dodge the attacks and then aim your boomerang through them to attack the monsters; then, slash at them. Hit both of them as fast as you can to prevent them from reviving each other.
Fight the big Fraaz one last time. Use the same strategy you used before: dodge his attacks and use them against him when he changes forms. He will change much faster this time, and his attacks will be more prolonged and powerful. When he is defeated, the Spirit Tracks in the Snow Realm will light up on your map and you will get another heart container.