Twinrova

Twinrova is the combined form of the witches Koume and Kotake and thus their elemental powers, fire and ice respectively. She first appears in The Legend of Zelda: Ocarina of Time. Twinrova is the penultimate boss in a few The Legend of Zelda games, including her debut appearance and the Linked Game for The Legend of Zelda: Oracle of Seasons and The Legend of Zelda: Oracle of Ages each. "Twinrova" is also used to refer to the duo on a general basis while battling. Compared to her split form, she looks much younger, though she keeps the olive skin and graying hair. She also wears a revealing top and baggy pants along with many drapes, and is abnormally tall. She wields two staffs, which are actually her split form's brooms.

The Legend of Zelda: Ocarina of Time
In The Legend of Zelda: Ocarina of Time, Koume and Kotake take on the form of Sorceress Sisters: Twinrova during the second phase of their boss battle in Spirit Temple. Twinrova attacks by either shooting a fire beam or an ice beam at Link. He can absorb their beam with the Mirror Shield, but after that, if Link tries to absorb the opposite beam, he takes damage. When the Mirror Shield absorbs the same element three times, it shoots back at Twinrova, damaging her. She then falls onto one of the four outer platforms, giving Link a chance to repeatedly strike her with his sword. After a while, Twinrova gets back up.

After taking enough damage, Twinrova is defeated. She splits back into Kotake and Koume, who begin arguing about their age difference despite being twins, as they float upwards into rays of light. Link is rewarded the Spirit Medallion for defeating the witches.

The Legend of Zelda: Oracle of Seasons / The Legend of Zelda: Oracle of Ages
In the Linked Game for both The Legend of Zelda: Oracle of Seasons and The Legend of Zelda: Oracle of Ages, Twinrova returns as Koume and Kotake's form during the second phase of the battle, which starts after each witch takes three hits.

Twinrova alternates between her fire form and her ice form, each having a different attack. If Twinrova is in her fire form, Link must avoid the lava pools that from around the area. If Twinrova is in her ice form, the entire floor is covered in slippery ice, and large ice clusters fly around the room and ricochet off the walls. After enough hits, Twinrova faces Link, revealing both her fire and ice side. Link can temporarily stun Twinrova by striking his sword at her enough times, then he can damage Twinrova by shooting either a Scent Seed or a Mystery Seed at her. After several hits, Twinrova is defeated, unable to sacrifice Zelda to revive Ganon, so she sacrifices herself instead.