Here's an interesting topic that someone brought up on another site:
Do the Sages in OoT die at the end of the game? I mean after we complete their respective temples, we don't see the Sages again except only in the Sacred Realm. If you think about, it does make sense in a way:
Saria: She enters the Forest Temple and captured by the evil inside. I am assuming she would've died due to the monsters in the temple.
Darunia: We last see him entering Volvagia's Lair in order to stop Volvagia. When we fight Volvagia, we don't see him again.
Ruto: We see her in the Water Temple float off to the top of the temple, but don't see her again after that. She might've been killed by the monsters in the temple.
Impa: She went off to the Shadow Temple in order to seal Bongo Bongo and the evil on the way. She probably got killed inside the temple once again.
Nabooru: We see her before fighting Kotake and Koume as an Iron Knuckle. But then the two Witches send her off to somewhere with a magical blast of some sort.
So that might mean the Sages at the end of the game are actually spirits and no longer own a physical body. I am not saying that any of this is true, but it is an interesting theory.
