There have always been rumours all around the Threetowns about the "Day of the hollow Sun". From what you have gathered you know that long ago, Arioch and his minions have tried to take over the towns. A mighty Necromancer and Priest, Dravin Rathul, aided Arioch in taking away the sun over the Threetowns. This phase of darkness lasted for many days in which the evil forces lead by Arioch himself tried to take over the towns and extinct all its inhabitants. Thats all you could find out there is no reference whether Arioch was stopped. You have serious doubts if anything like this has ever happened, or if the rumours are only a frightening prophecy. Even the different parts of armory that can be found all over the world, that can doubtless be connected to the "Hollow Sun Cult", can not certify either version. Yet there is a small underground cult that worships Dravin and his vision of the sunless sky. They are persecuted by the authorities of course, but somehow seem to be able to settle in some faraway corners of the towns and even harata. This armor is so powerful and richly decorated that one can only assume it was designed to serve high ranking members of Dravin's organisation. The wearer seems to be protected by shadows swirling around the dark parts of the armor.