"Not all heroes are righteous — none of them is incorruptible. With the Antipaladin and the Oath of the Archdevils, you’ll be the antihero of the world’s greatest roleplaying game.
Oath of the Archdevils
The most terrible enemy is the one you called brother. Corrupted by sin and thirst of power, mad or beguiled by the lord of hell promises, some paladins abandon the way of light to embrace the darkness. They act as spies, infiltrating through the mortal society to plot and realize the plans of their devilish masters. At the height of power, some of these black knights become ambassadors of the Nine Hells, liutenants of the damned on earth.
Each of these fallen paladins dedicates all his mortal life to the service of an archdevil, the lord of a circle of the Nine Hells, hoping his slavery on earth is worth a place of honor in hell.
Regardless from the Oath they choose to swear, all paladins are cohorted to fight against the evilforces. In opposition to the antipaladins who are the evil forces. Where a paladin is committed to defend the weakest ones, an antipaladin takes advantage of their weaknesses. During the darkest hour, when a paladin fights to bring the light, the antipaladin casts new gloom.
He is the embodiment of evil, a bearer of maladies and despair. He fights everyone who hinders him with bloodlust and treachery. He has no qualms to betray someone for his benefit."