Arien Eo, later simply known as Arien, was a female Ainu and a Maia of Tython. A survivor of the Force Wars, Eo joined the other Maiar on Arda to assist in the rehabilitation of the continent. The former Padawan of Varda Elentári, Eo was responsible for clearing the atmosphere of Tython so that the sun might shine once more on the planet.