King Dodongo

King Dodongo, the Infernal Dinosaur, is the boss of the dungeon Dodongo's Cavern in The Legend of Zelda: Ocarina of Time.

In-game
King Dodongo is encountered at the end of the Dodongo's Cavern dungeon. He is in a small, circular room with a large pool of lava inside, and the battle takes place on the strip of ground surrounding the lava. His main attack is to breathe fire, and when he opens his mouth to prepare for this attack, Link can throw a bomb into his mouth, and when he swallows it, it goes off, stunning him and leaving him vulnerable for attack. At this point, Link can hit him with his sword or even a Deku Stick. After being hit like this once, King Dodongo curls into a ball and rolls around the perimeter of the lava, attempting to ram into Link. Link can either stand in the far sides of the room, near the Bomb Flowers, or hold up the HYlian Shield while he rolls to avoid taking damage. Once he is hit around three times using the bomb technique, he dies, trying to roll into Link but falling into the lava, which hardens and on which then spawns the Heart Container.

Trivia

 * As his name implies, King Dodongo is king of the Dodongo creatures, but there may have been Dodongos even larger than him, supported by the huge Dodongo skulls and bones littering the dungeon.