Incendax said:The Blood Mage ability is definitely a precident for damaging yourself. It is also a Free Action. If you wanted to keep it a free action I'd definitely say 1d10 damage for a 'minor' wound. However, maybe a compromise would work in the sense that you would have to use the Minor Action to get the benefit, but in such a case you could use whatever weapon you had handy (Dagger 1d4 or Unarmed Attack 1d4).
Well I'd say the blood mage's free action is a class feature. In fact if this were to actually come up in game I might be inclined to make stabbing yourself a standard action. Certainly it's a standard action to stab a monster.