Editing Elder Evils (section)

===[[Sertrous]]===
Sertrous was a powerful [[Obyrith]] that was killed in the distant past, but whose spirit clings to life in his severed skull. He was first killed for refusing to serve [[The Queen of Chaos]] but his spirit escaped to the material plane where he possessed a snake and made it into his new body. After he sent armies of snakes and monsters to attack mortals because he was jealous of the worship the gods received from them, he was then killed again by a Solar named Avamerin, but not before Sertrous revealed the secret that divine magic is possible to gain from any kind of faith, not just faith in a god. Avamerin at first didn't understand what Sertrous had said and shared the words with others, and when godless clerics started appearing as a result he was punished by being demoted to a Planetar. Avamerin then turned on his god and began working to bring Sertrous back to life. Avamerin now leads a cult of heretical [[Yuan-ti]] called The Vanguard of Sertrous that claims Sertrous is the true creator of the Yuan-ti. As Sertrous gets closer to returning to life, encounters with snakes and snake-like monsters become more and more frequent. Sertrous does not have stats because he is nothing but an immobile skull, but the players may fight against a CR 23 aspect of Sertrous.

In the suggested campaign, the players are hired to find out why a merchant has cut contact with his business partners and discover that he has fallen under the sway of a group of Yuan-ti who are lead by somebody named Seghulerak (Yuan-ti abomination, level 10 cleric, level 5 thaumaturgist) and do not worship the traditional Yuan-ti gods. Seghulerak and the Vanguard of Sertrous seize control of a major Yuan-ti city and start setting up ''serpentgates'' in temples around the world from which to launch invasions. The players investigate an infestation of snakes and interfere with the creation of one of these gates. The players eventually makes their way to the city where the Vanguard of Sertrous is based after many battles against Yuan-ti and other snake monsters and defeat Seghulerak, but her body vanishes when she is killed, leaving behind a pile of dead headless snakes. After some investigation the players learn about the Serpent Reliquary, an extradimensional temple that is the true base of the Vanguard. The players locate the portal the Reliquary and defeat Seghulerak again. After this they meet Avamerin, who will try to trick the players into leaving by lying that Sertrous never existed and this was all a test by the gods. If the players attack and defeat him, he is transformed into the aspect of Sertrous which the players must destroy. If the players are dumb enough to fall for his trick, he might send them to a layer of the abyss disguised as their home.
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Sertrous aspect.png|Aspect of Sertrous
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