Kotake and Koume
From SmashWiki, the Super Smash Bros. wiki
Kotake and Koume (コタケ, Kotake, and コウメ, Koume) are characters from the The Legend of Zelda series.
Kotake and Koume are twin Gerudo sisters and the adoptive mothers of Ganondorf. They are witches with elemental powers—Kotake's are ice based, Koume's are flame based—and they fight Link in Ocarina of Time as the boss of the Spirit Temple. During the first phase of the battle, they fight separately, but in the second phase, they merge into a single, younger-looking being named Twinrova. They later appeared as a boss in The Legend of Zelda: Oracle of Ages and The Legend of Zelda: Oracle of Seasons in a somewhat similar fashion.
The twins appear on the Gerudo Valley stage in Super Smash Bros. for Nintendo 3DS. They appear once the bridge has been broken, after which they fly around the stage before randomly setting either the left half of the stage on fire, or creating ice spikes on the right side. This effect is only temporary, and forces all fighters to one side of the map.
Koume and Kotake reappear on the Gerudo Valley stage in Ultimate, behaving the same as they did in Super Smash Bros. for Nintendo 3DS.
The twins also appear as a spirit, along with Twinrova as an enhanced form.