Eras

Eras, also referred as the Druidon Tribe's Great Power, is the main antagonist of Kishiryu Sentai Ryusoulger and the mysterious leader of Druidon Tribe.

They are revealed to be sealed underneath the crust of the Earth, and only pulling out the Ryusoul Calibur could awaken them. They are referred as master by both of the active lead Druidon Generals on Earth, Pricious and Wizeru.

Past
Nothing much is known about Eras, his true form or his ability for now, aside from being the master of Druidon generals and started the tyranny upon the Earth 65 million years ago. They were sealed within the crust of the Earth after the Ryusoul Tribe rebelled against the Druidon Tribe and defeated them, with his generals escaped into the space.

Kishiryu Sentai Ryusoulger
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 had been discussing about RyusoulCalibur. Pricious revealed that as soon as Ryusoul Calibur was pulled out, the Great Power of Druidon would be awaken. Horrified, Wizeru realized that Pricious intended to revive Eras. Kureon, who attempted to become a top general of Druidon, was displeased when he learned about Eras' existence and decided to eradicate Ryusoulgers in order to get promoted.

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 Ryusoulgers' Episode 40 and is never mentioned or alluded before that point.
 * Due to being the leader of Druidon Tribe, his chess motif is based on a king piece.