Poison Tolerance - From years of working with poisons, the thief/assassin has become less susceptable to their effects.

I thought of this idea from the stories where people would eat small doses of poisons and eventually become immune to them. This would be appropriate for assassins and poisoner thieves.

Obviously, giving a poison resist flag would be way too powerful. Maybe it makes it harder to get poisoned, or poison does less damage, or it lasts a shorter duration.

I've got something along these lines for poisoner thieves down in my little pile of thief edges that may someday see the light of day.