Diababa

Twilit Parasite: Diababa (覚醒寄生種 ババラント, Awoken Parasite: Babaranto) is the boss of the first dungeon, the Forest Temple, in Twilight Princess. The boss itself is made up of two large plant heads that resemble Deku Babas and one massive plant head with a hidden eye inside its mouth. The appearance hints Diababa may have originally been a Deku Baba which touched the Fused Shadow.

Strategy
The beginning of the fight starts with only the two smaller heads. Bomblings can be seen perched on logs floating in the water, and the objective is to use the Gale Boomerang to make them collide with each of the two heads. A single hit will defeat each one.

The second phase of the fight begins when the larger head bursts out the water. After a few seconds, Ook appears and swings across the room carrying Bomblings for Link to use to stun Diababa's middle head, leaving its eye (the critical point) open for Link to attack with his sword. Upon recovering, Diababa sprays poison at Link, so he must move quickly to dodge it. The two smaller heads also continue to attack occasionally. As Link continues dodging its attacks and repeats the process, Diababa is eventually defeated.

Upon Diababa's defeat, Link receives the first of the three Fused Shadows and a Heart Container.

Trivia

 * Diababa resembles Big Manhandla, the guardian of the Sea of Trees in Four Swords. It has also a slight resemblance to Kalle Demos from The Wind Waker.
 * Inspiration for Diababa may have come from Flaahgra from Metroid Prime, a giant mutant plant who resides in polluted water; the two foes also share a battle strategy involving bomb-like attacks. Another possible inspiration is Biollante of the Godzilla film series.