While the threat, or even certain knowledge, of discovery will dissuade some Kindred from breaking an Oath, others are willing to brave the anger of their superiors, sure that they can run or hide. The Oath of Blood Knives imposes mystical punishment at the moment of violation, ensuring that an Oath-breaker cannot get away without penalty. The power behind the oath comes from a Devotion, which may be used by anyone present at the swearing.
While the Kindred swearing the oath must be doing so voluntarily, he need not be voluntarily submitting to this Devotion. That is, the Devotion can be used on a Kindred who is swearing an oath by writing a text in his own blood, even without his knowledge. Invictus stories tell of Tadeus the Just, an ancient member of the covenant who travels the world incognito, imposing this oath or its more powerful variant, the Oath of Burning Blood, on Kindred who swear oaths that they intend to break.
The Oath of Blood Knives must be sworn willingly by a Kindred who donates the point of Vitae needed to activate the Oath. Such an oath cannot be sworn while under mystical compulsion; the Kindred’s will must be truly free. A Kindred can seal his own Oath with the Discipline, but it is normal for the beneficiary of the Oath to do so instead, as otherwise there is no evidence that the Devotion has been used.
As with the Blood-Tell Oath, the Oath of Blood Knives requires a text written in the blood of the Kindred swearing. This blood remains fresh until the Oath is broken or the swearing Kindred suffers Final Death. In addition, if the swearer violates the Oath, he immediately takes a number of points of lethal damage equal to the number of successes on the activation roll, and loses the same amount of Vitae. The damage is caused as the Kindred’s own blood forms into jagged shards and cuts its way out of the foresworn body. (A Kindred with insufficient, or no, Vitae remaining still takes the full damage, but cannot lose more Vitae than he has.) There is no resistance roll allowed, as the Kindred voluntarily took on the Oath. The subject of the Oath has no idea how many successes were rolled, and thus does not know how much damage he risks. If the activation roll fails, the Oath functions as a Blood-Tell Oath.
The effect of the Devotion ends when the subject breaks the Oath, thereby taking damage from it, or when the Notary or the lord releases the subject from its effects by blotting out the written oath with one Vitae of his own.
