A One-Round Faction Adventure Packet for 13th to 16th-Level Characters
From the introduction:
Millennia ago, during the Age of Demons, the mighty couatls ruled Xen’drik. With the help of the Dragons, they defeated and imprisoned the rakshasa rajahs in a war that lasted thousands of years. Ultimately, the couatls sacrificed most of their number, sealing the rajahs in prisons holding their combined souls.
The locations of these prisons have long since been forgotten, but while the wards that held each paired couatl and rajah were meant to be permanent, some have weakened in the ensuing years. Two-hundred years ago, a green dragon scholar, Hruuagoryn (HUH-ROO-OO-AH-GORN), discovered a trace of one such prison woven into the draconic prophesy and slowly began to work his way back through the prophesy to find its location and study it. The mere act of discovering the existence of the prison weakened the bonds holding the rajah and its captor, allowing parts of their soul to “bleed” into Eberron.
The couatl’s spirit set about to keep the location of the prison hidden, while the rakshasa conspired to force the prison’s discovery — with the ultimate goal of freedom. In doing so, both discovered Hruuagoryn’s mind, and fought for control of it. The rajah promised eternal life in exchange for performing a ritual to free him, and the couatl promised riches in the afterlife for performing a ritual to re-seal the prison. Eventually, the scholarly dragon was driven insane. Several months ago, he callously slaughtered the tribe of Argonnessen barbarians who worshipped him and fled to Xen’drik to find his dueling masters’ hidden prison.
He found the tomb, only to discover the outer temple was inhabited by a tribe of amphibious yuan-ti, drawn to the location by whisperings of the joined Silver Flame. In such proximity to the source of the voices in his head, Hruuagoryn promptly lost the last shred of sanity he had, giving into the demon’s voice, and now alternates between pacing at the outer-most ward of the prison and joining the yuan-ti in their worship of the vestiges of the couatl and rajah majesty present in the temple.
Recently, the seren clan leader of Hruuagoryn’s old tribe — a dragon shaman named Mehmet — returned from a mission on Xen’drik to find his tribe destroyed and evidence leading him to discover their dragon’s betrayal: Demon worship. He is the last of his tribe, and had nowhere else to turn, so he approached Blackwheel with a proposal: help him hunt down and kill the rogue dragon scholar, and he will give them the secrets to interpret the remaining Caldyn Fragments.