Traits are characteristics of a Temtem Species that have some effect in battle. Most Temtem can have one of two different Traits, while some only have one. Temtem can only have either positive or negative Traits. When evolving, many Temtem acquire a new set of Traits. The trait of the evolved Temtem will be the one placed in the same Tempedia's slot as the trait of the unevolved Temtem.
While normally selected by random when a Temtem is born via Breeding, certain gear items can force a parent to pass down its trait to an offspring.