Eras

Eras, also referred as the Druidon Tribe's Great Power, is presumably the main antagonist of Kishiryu Sentai Ryusolger and the leader of Druidon Tribe. They are revealed to be sealed within the core of the Earth, and is referred as master by both of the active lead Druidon Generals, Pricious and Wizeru.

Overview
Nothing much is known about Eras, his true form or his ability aside from being the master of Druidon generals and led the tyranny upon the Earth 65 million years ago. They were sealed within the core of the Earth after Ryusol Tribe rebelled and defeated him, with the generals of the Druidon Tribe escape into the space.

In modern era, the Druidon Tribe returned back to the Earth in order to reclaim it. After the second and final death of Gachireus, the Druidon generals on Earth sensed that Eras was awakening.

Trivia

 * Eras' debut is a sphere-shaped core, which made them similar to previous villain leaders including Shine, the Omnipotent God and Evil Electro-King Javious I, that all lacked a mobile form in their full appearance. However, it is suggested that Eras would have a mobile full form once he was resurrected.
 * Eras has one of the latest debut appearances made by Super Sentai villain leaders by making his debut in Ryusolgers' Episode 40 and is never mentioned or alluded before.