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Title(s) The Arch-Lich, the Chained God, the Maimed God, Master of the Spider Throne, the Whispered One, the Dying King, the Lord of the Rotted Tower, the Undying King
Home plane Prime Material (Oerth)
Power level Lesser
Alignment Neutral Evil
Portfolio Destructive and Evil Secrets, Magic, Hidden Knowledge, Intrigue
Domains Evil, Knowledge, Magic
Symbol eye in the palm of a left hand
Vecna is usually depicted as a powerful magician resembling a desiccated corpse missing his left hand and eye. A constant theme in the adventures in which the character appears is Vecna's never-ending quest for power, ending, should he succeed, with Vecna as the only deity in existence.
Scriptures Being a secretive cult, there are no real collections of Vecnan teachings. However, copies of the Book of Vile Darkness are highly prized by the cult for Vecna's role in that work's development. The Open Grave book offers the "Scroll of Mauthereign", which offers a twisted version of Vecna's history and tells his followers that committing evil acts is a holy and righteous act.
Vecna's cult is very secretive, and cells have been uncovered, at various points in history, in Diamond Lake, Greyhawk, and Verbobonc. Temples to Vecna have also been reported in the Pomarj town of Highport and Erelhei-Cinlu, the debased city at the heart of the Vault of the Drow.
Each position in Vecna's cult is named for a certain body part. At the top is Vecna himself, followed by the Voice of Vecna, which can only be filled by Vecna's manifestation.
Next is the Heart of Vecna, the high priest of the cult. The last known Heart of Vecna was Diraq Malcinex of Ket, who was slain by adventurers in 581 CY. Immediately below the Heart of Vecna are two bizarre monsters known as the Hand and the Eye. The Eye of Vecna creature appears as a slender humanoid with an eyeball for a head, whereas the Hand of Vecna appears as a stocky humanoid with a huge left hand where its head should be. Individual congregations are known as organs. Each organ is led by a Thought of Vecna. Lesser priests are known as Memories of Vecna.
Lay members of the cult consist of the Teeth, Fingers, Blood, and Spawn of Vecna. The Teeth of Vecna are made up of wizards, and specialize in arcane spellcasting and crafting magical items for the cult. The Fingers of Vecna consist mainly of thieves, who engage in various forms of subterfuge. The Blood of Vecna are mainly warriors charged with protection and enforcement of the cult and its goals. The Spawn of Vecna are the lowest in the cult hierarchy, and consist of the common people who honor the Lich Lord.
In 4th edition, the Open Grave book shows the leader of the cult of Vecna is a Lich named Mauthereign. Even when Osterneth, the Bronze Lich, is Vecna's mightiest servant, her position is not revealed among his files.
Other Vecnan organizations
Other Vecnan organizations are known to exist outside of the mainstream cult, and some may have similar or identical names. Relations between these groups and the mainstream cult may vary. Known examples are the Eyes of Vecna (a cult of undeath consisting mainly of rogues), the Fingers of Vecna (Vecna's personal guard), and the Ebon Triad (a heretical cult seeking to merge Vecna, Hextor, and Erythnul into a single entity). In 4th edition, a secret group known as the Keepers of the Forbidden Lore is devoted to Vecna. Unlike most Vecna worshippers, the Keepers reject most of the nasty and evil rituals and beliefs associated with the God; they worship Him as the God of Secrets, and believe that there is some knowledge too evil for the world to know. They instead hunt down secrets and information they deem to be too dangerous for the world at large and keep it secret in the name of Vecna. This puts them in opposition to mainstream followers of Vecna who regard the Keepers as heretics, and makes them enemies of Ioun and her followers, who believe all knowledge should be available for everybody and the moral obligations on how to use it rest on the shoulders of the individuals involved.
Copied from Wikipedia http://en.wikipedia.org/wiki/Vecna