Giant Ghini - Spirit Dungeon Mini Boss
Strategy: Destroy the smaller ghosts with your sword if they get too close, as they will slow you down if they attach themselves to you. The Giant Ghini can be defeated by a simple sword attack as well.
Pumpkin Head - Spirit Dungeon Boss
Strategy: Attack Pumpkin Head's body with your sword until it disappears, then pick up the pumpkin with the Power Bracelet to make a ghost appear, and toss the pumpkin as far from the ghost as possible. Attack the ghost with your sword as many times as you can before he gets back to the pumpkin. Repeat this process until Pumpkin Head is defeated.
Swoop - Dungeon of Wings Mini Boss
Strategy: Stay on the blue tiles in this room. When Swoop crashes down onto the floor, he will break any tiles not colored blue. Keep moving and changing directions to keep him from landing right on you, and attack with your sword immediately after he lands. When he is nearly defeated, Swoop will start to bounce around after he lands, so be careful.
Head Thwomp - Dungeon of Wings Boss
Strategy: Head Thwomp has four faces, red, blue, green, and purple. To defeat him, you will need to ride the moving platforms and drop a bomb down the top of his head when the red face is showing. If you hit him successfully, he will start spinning faster and stop on one face for a moment. If the he stops on red, you will get a heart, and Head Thwomp will take damage. Any of the other colors cause him to attack in a different manner. Four hits to Head Thwomp's red face will defeat him.
Subterror - Moonlight Shrine Mini Boss
Strategy: Subterror is a mole who burrows underground. To beat him, use the shovel to dig him up, then slash him from behind or from the side with your sword. After repeating this process, Subterror will be defeated.
Shadow Hag - Moonlight Shrine Boss
Strategy: Avoid the shadows in Shadow Hag's lair as they cause damage. When they converge in one spot, Shadow Hag will appear. That is your clue to get ready to attack the moths she releases. After all four moths are defeated, she will charge you from behind. Do NOT turn around, or Shadow Hag will disappear. Instead, use the Seed Shooter to bounce a Scent Seed off the wall, directly to Shadow Hag. Repeat this process five times, and you will defeat Shadow Hag.
Armos Warrior - Skull Dungeon Mini Boss
Strategy: The Armos Warrior will throw his sword at you, while moving around with his shield raised. Try to move so that his sword hits him, which will eventually destroy both the sword and his shield. After this happens, he will start charging you. Wait for him to pause for a second, then attack with your sword.
Eyesoar - Skull dungeon Boss
Strategy: Destroy the small eyeballs first by hitting them when they stop orbiting around Eyesoar. When they're defeated, use the Switch Hook to attack Eyesoar himself. This will stun him, so quickly run over to Eyesoar and strike him with your sword as fast as possible. Repeat this process a few times.
Smasher - Crown Dungeon Mini Boss
Strategy: Avoid the ball Smasher will throw at you, then pick it up with your Power Bracelet and throw it at him. This is the only way to cause damage to Smasher, so make sure you have good aim.
Smog - Crown Dungeon Boss
Strategy: To defeat smog, you will first need to use the Cane of Somaria to create blocks that willl cause the smaller clouds to collide and form Smog. After doing that, a simple sword attack is all it takes to defeat Smog.
Vire - Mermaid's Cave Mini Boss
Strategy: When you get close to Vire, use your sword, spin attacks are the best. When he shoots a fireball at you, just deflect it with your sword. When Vire is almost defeated, he will start to keep his distance from you, but just be patient, and he will come within striking distance again.
Octogon - Mermaid's Cave Boss
Strategy: Use the Seed Shooter to hit Octogon in the small mouth on his red side. The white side is invulnerable. When Octogon goes underwater, bounce the seed off the walls so that you don't have to turn around.
Angler Fish - Jabu-Jabu's Stomach Mini Boss
Strategy: Make the Angler Fish fall to the bottom of the pool by shooting him with Scent Seeds. When he drops to the bottom, start hitting his antenna with your sword as quickly as possible.
Plasmarine - Jabu-Jabu's Stomach Boss
Strategy: Just after Plasmarine shoots at you, use the Long Hook, causing you to switch places with him. If timed right, this will cause Plasmarine to run into his own attacks. Do this several times to defeat him.
Blue Stalfos - Ancient Grave Mini Boss
Strategy: Blue Stalfos will shoot a energy ball at you, which you should deflect back at him with your sword. When they hit him, he will turn into a bat for a little while. Strike the bat with your sword as rapidly as possible.
Ramrock - Ancient Grave Boss
Strategy: To defeat Ramrock, you will need to follow a different strategy depending on how he attacks you. When Ramrock's hands separate from his body and come towards you, attack them with your sword. When his hands are to the side of his body, drop a bomb between his hands so that it explodes right when they touch. When his arms form shields, use the Seed Shooter to hit him in the top of the head, and finally, wait for him to toss one of his hands at you, and then quickly pull the other one as far back as you can by using the Power Gloves. Let go, and his hand will fly back and hit him.
Veran's First Form - Tower of Darkness Boss
Strategy: Use Roc's Feather to avoid Veran's fireball attacks, and use the sword to attack.
Veran's Turtle Form - Tower of Darkness Boss
Strategy: Avoid Veran until her face shows, then attack with your sword.
Veran's Queen Bee Form - Tower of Darkness Boss
Strategy: Jump over the stingers that Veran shoots at you, then attack with your sword. If you run low on hearts, defeat the swarm of bees that Veran will summon from time to time.
Veran's Spider Form - Tower of Darkness Boss
Strategy: Stun Veran with bombs, then attack with your sword.
Koume and Kotake - Password Only
Strategy: Use your sword to reflect the attacks of one witch at the other one.
Twinrova - Password Only
Strategy: Use a spin attack to halt Twinrova's attacks, then use Scent Seeds to damage them.
Ganon - Password Only! True Final Boss of the game!
Strategy: Unless you have the Master Sword, you will need to use spin attacks on Ganon. Wear the Red Ring or Spin Ring if you have them to cause as much damage as possible. Jump to avoid Ganon's attacks, and if the room starts shaking, jump again and hit him with a spin attack.