Mark of Nessus

(Fiendish Codex II: Tyrants of the Nine Hells, page 84, DnD 3.5)

[General]

All bow before Asmodeus. The Lord of Nessus grants you a hint of his commanding nature.

Prerequisite

Brand of the Nine Hells, allegiance to Asmodeus

Benefit

Few have the resolve necessary to confront Asmodeus himself, and you have learned to tap into this commanding authority. Whenever a creature would attack you, target you with a spell, or use spell-like or supernatural ability against you, it must first succeed on a Will save (DC 10 + 1/2 your HD + your Cha modifi er). If it fails, it must select another target or take some other action. Once an opponent succeeds on the saving throw, it cannot be affected again by your Mark of Nessus for 24 hours. In addition, once per round as a swift action, you can infuse a single natural attack with hellfi re, dealing an extra 1d6 points of damage.