Cult of the Lidless Eye (5e Other)
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"A Human-dominated cult that worships Beholders" is probably the most accurate description of the Cult of the Lidless Eye. The Cult, broken up to cells, is a mainly hierarchical cult that, interestingly, tolerates visitors who must follow a strict set of rules. The Cult ranges in size, from group that assemble in rooms, to entire towns, such as the town of Burningvale.
The chain of command
The chain of command is very loose, as the proper commanders are not exact. Generally, this is the chain observed: Avatars, Cult Lords, Dread Guard, Greater Cultist, Minor Cultist and Lesser Forsaken at the bottom of the chain. Sometimes, a Forsaken does something worthy of the Lidless Eye's attention. This results in an occasional Greater Forsaken which is below Dread Guard and above the Greater Cultist. Occasionally, Cult Lords may be at the top of the chain due to Avatars being less reliable.
The signature spell
All groups have a particular symbol or skill specific to them. The Cult of the Lidless Eye is no different. For them, their signature is a curse known as Sinister Sleepwalking, which ultimately results in complete control over the victim, over a course of about 100 days.
Avatars of the Lidless Eye
Every major and some minor cell of the Cult of the Lidless Eye has an Avatar of the Lidless Eye, which is a Beholder sent by the Lidless Eye, that oversees them. A peculiarity of the Cult is that they are allowed by their religion to kill the Avatar if the Avatar does not succeed in leading the Cult properly, unlike most religions.