Backstabber (General)

You know how to exploit the trust of others for your own ends.

The Gates of Hell (Dice Freaks)

Grimoire of Cosmic Entities Volume One By Eli Atkinson, William Church and Serge W. Desir, Jr.

Original Concept by Serge W. Desir, Jr.

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Prerequisites: Impostor

Benefits: You gain a +2 bonus on Bluff checks. Any time you hit an opponent in combat when they are flat-footed, flanked, or otherwise denied their Dexterity bonus to armour class, you deal an additional 2 points of damage. If a ranged attack, the opponent must be within 30 feet to take the extra damage. Creatures immune to critical hits are likewise immune to this damage.

The damage dealt with Backstabber stacks with sneak attack damage.