The Oracle's Current. The Oracle, #6

Lichen grew up dreaming he was going to test into the Earth Caste. But when he walked out of the testing chamber with the brown hair of Earth and the blue eyes of Water, he knew something had gone terribly wrong. Instead of his dream, he tested into the elusive Ether Caste, which made him both a cherished wonder and a pariah. Unable to handle the strange mixture of adoration and abhorrence from his peers, Lichen leaves the Monastery with the hope of finding some sort of happiness. But, when tragedy strikes the Monastery, Lichen fears he won't be of much help.
He still wants to lend a helping hand, or at least a shoulder to cry on, but the quest the Oracle sends him on instead is much more important-so important, in fact, that dying to ensure the success of his mission is a real possibility.