Each time a character who is not chaotic evil uses a power with a corruption effect, he or she must immediately make a saving throw. On a save, the character takes 5 damage per tier. On a failed saving throw, the character gains 1 corruption point. When a character’s corruption points equal his or her highest ability modifier, the character’s alignment shifts one step toward chaotic evil (lawful good to good, good to unaligned, unaligned to evil, or evil to chaotic evil). The character’s corruption point total then drops to 1 + 1 for each time the character’s alignment has shifted.
A character can remove any corruption points gained by using the Remove Affliction ritual, undergoing a quest for atonement, or some other powerful magic as the DM decides.
Dungeon Masters should consider adding corruption effects to other aspects of their vile darkness campaign. For example, a DM might rule that a character with the cultist theme who uses ritual sacrifice to kill a helpless prisoner has gained a corruption point. The slow but inexorable slide into wickedness and depravity can be modeled with corruption effects.
Published in The Book of Vile Darkness, page(s) 83.