Dark Link. To defeat him use either the Megaton Hammer or Din's Fire.
Electrocute him.
Yes. He is the mini boss in the water temple.
After defeating the mini-boss in the Water Temple in "The Legend of Zelda: Twilight Princess," you obtain the Boss Key. This allows you to access the main chamber of the temple where the final boss awaits. You will then need to navigate through the temple's puzzles and enemies to reach that chamber and face the boss. Be sure to explore the area for any items or upgrades before proceeding!
The water temple's boss is Morphia, an eye with tentacles made of water.
a white monkey with a golden mask
Defeat the mini-boss in the Goron Mines (2nd temple)
It is somewhere in the where in the Wind Temple
The room with the Deku Toad, the mini boss.
You finish off the forest temple mini boss
You get it in the sky temple when you beat the mini boss.
First, you have to enter the room where the green Poes Sister is hiding. Then go downstairs and enter the room there. The mini boss is 3 Stalfoes.
You have to beat the mini-boss in the first temple, which is Ook, a white monkey