Only usable by an acting vampire.
[san] strike: steal X blood. X is the number of untapped Blood Brothers of the same circle.
[SAN] strike: steal 1 blood. If at least one blood is succesfully stolen, attach this card to this Blood Brother. They gain one level of a discipline the opposing vampire has at least one level higher.
Maybe this would give Blood Brothers more reason to start a combat other than to weaken the opposing vampire.
I'm not really seeing how the card would do that.
At inferior, it weakens the opposing vampire. It weakens them differently to playing a ton of Potence and whacking someone into torpor, but an empty vampire is still weakened. There are ups and downs - you get blood, but they don't go to torpor without more effort, and you could have got most of that blood (slightly delayed) from Taste of Vitae. And since you're not making a hand strike, you can't play Immortal Grapple - so they can S:CE. But assuming that the card is playable, the vampire is weakened.
At superior, it's very random. Does the vampire have a discipline you want, and do they have it at a higher level? There's no real point getting a point of Auspex if you have no Auspex cards in your deck, and there's little point putting Auspex cards in your deck on the off-chance that they might turn up. So then your options are most likely Potence or Fortitude. If you're not beating vampires up so much, another level of Potence isn't that helpful to you - and if you are beating them, inferior Potence is just fine much of the time, as you get the goodies from both IG and Disarm.
Since you have to be acting, it also seems to waste a good opportunity to push a vampire into torpor, unless you throw in additional strikes (e.g. Octopod). At which point, it's not so much a reason to start a combat other than weakening your opponent as something to do alongside weakening your opponent.
So, I'm underwhelmed by the card's power, but also that it doesn't seem to be doing what you want anyway.
Submission: Taken by force
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