Twinrova

You first see these witches after completing the Spirit Temple as a child. They are seen sucking Nabooru into a vortex and fly into a vortex. As an adult they order an Iron Knuckle to fight you, afterwards you find a brainwashed Nabooru under the armor.

Twinrova is the name of the two sorceress sisters that inhabit the Spirit Temple. They are Koume, Sorceress of Flame, and Kotake, Sorceress of Ice. To defeat these two powerfull witches, you must use your Mirror Shield to reflect Koume's attacks at Kotake, and vice versa.

Once they've been hit a few times, they will combine into one powerfull witch, who can attack with both fire and ice magic. To defeat this form, absorb three attacks of the same element with your mirror shield. You will then automtically fire that element from your shield. Hit Twinrova with this, and she will be stunned, so that you may let her feel your sword.

After Twinrova has been defeated, you may claim a Heart Container and free the Sage of Spirit.

They also appeared as the second to last boss in Oracle of Ages and Oracle of Seasons.