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Self-sacrifice allows a mage to use Prime 1 in order to draw upon his personal life-force; by cutting himself, pushing the limits of his endurance, working himself to exhaustion, or otherwise inflicting damage upon himself in order to draw upon his life-force, that character can “give till it hurts.” Each success on the Arete roll moves one point of Quintessence from the mage’s Pattern into the task at hand, lowering his difficulty at that task by -1 per point. (At the Storyteller’s discretion, this feat might allow the player to bend the usual -3 modifier limit; the usual limits on magick-roll difficulties, however, still apply.)

In game terms, a mage has 10 points of Quintessence in addition to that character’s Avatar Background and/ or his current Quintessence rating. Each of those Quintessence points translates to one health level, with the last three taking that mage below Incapacitated. If he uses those points, then he dies.

Damage inflicted by “heart’s blood” self-sacrifice can be healed only by time and rest, not by magick. And so, you probably won’t want to go beyond the Bruised level unless your mage is desperate enough to do whatever must be done.