Como isso já passou 36 horas sem resposta, expandirei Comentário de Garret Gang em uma resposta. O livro é Um Mundo sem Heróis da série Beyonders de Brandon Mull. As pessoas que morrem e são reencarnadas são as Amar Kabal. No capítulo 18, Jasher diz a Jason e a Rachel:
Jasher paused, regarding them with icy blue eyes. “‘Amar’ means ‘seed.’ The Amar Kabal are the People of the Seed.” He turned his head and lifted the roll of hair. At the base of his skull was a raised portion of flesh the size of a walnut.
Jason winced. It looked like a huge cyst. “What’s it for?”
“The amar is the vehicle of our immortality. It dislodges at our death, granting new life when planted in the earth.”
“You mean you grow?” Rachel asked in amazement. “Like a plant?”
“Buried in fertile soil, the man grows from the seed within a few months. Less fertile soil requires more time. If my seed dislodged in extremely arid terrain, I might never be reborn."
E há realmente uma cerimônia para marcar sua primeira morte:
Jasher laughed as if the idea were absurd. “No, we are reborn into the prime of adulthood, the age at which we first die. Our First Death is a ceremony held around age twenty."