Era Star

Era stars are earned by completing generated objectives for your culture. Era Stars are spread across seven categories that correspond to the seven culture affinities: Aesthete, Agrarian, Builder, Expansionist, Merchant, Militarist, and Scientist. There are 3 era stars to unlock per category in an Era and the era stars that match your culture affinity will yield you twice the amount of. These categories includes several minor objectives such as building extensions and claiming territory, as well as a main objective which is determined by the one of seven gameplay orientations for your culture. These objectives can be completed multiple times with increasing requirements. Upon completing an objective you will earn an era star and some.

Competitive spirit era star
When an Empire is the first one to enter a new era, its opponents unlock this era star category. This catch-up category will passively grant you era stars each until you unlock the next era. Era Stars will unlock faster as more Empires reach the next era. Note that this era star category will be reset and removed when entering a new era, and that it does not grant any.