The Cult of eyes is mortally just urban legend during present time. there are no records or reports of them for the past few centuries. The only evidence of their practice is the occasionally eyeless corpse that turns up in the wilderness.

The only reason they are known at all is due to the destruction of Nabilhime where three Beholders under cult flags followed by a small army of followers lay siege to the fortress city and left it in ruins overnight. its not known why they invaded or how such a formidable fortress was brought down over night.

Members of the Cult believed that our current sight is an illusion, underdeveloped. Mortals have yet to truly see.

Members wear blindfolds or other eye coverings as a show of Devotion, the most devoted have their eyes removed and are normally gifted with proper sight by their leaders. (Adavanced blindsight)

They follow the Beholders Sharax, Vorg and Gomen who in turn follow the watching Old God. All server under is everlasting gaze

It’s true that the leaders of the cult are the trio of beholders however due to their tendencies to hold up with rituals and research a type of Pope was elected.
A humanoid figure but far from human, with eyeball covering its arms and face that it keeps covered with bindings. It wears a large metal crown of sorts that takes similar looks to a helmet or cage. This creature goes by the name of Nicorash.

Nicorash was once one of Professor Stem’s most promising students, however he stopped his studies and left so close to graduating that it throw a lot of questions up into the air, however follow ups were not successful as he seemed to have vanished.
Nicorash is very much mad but in a somber and philosophical way, all he speaks is madness but at the same time makes complete sense.

The cult often kidnappes people of any kind to steal their eyes and offer them as sacrifice to their God.

A sect of the cult is destroyed by a Paladin known as Sir Viktor and an unknown Drow (at least 10 years before the beginning of campaign 10)