The Black Swan is a curse that was created by the legendary Saberhagen, and has been cursing generations of humans all for the sake of killing the vampire king. You receive a copy of this curse, although it is slightly changed from the original one, as it offers only benefits and takes away any of the drawbacks. Some of the most notable changes that you receive are a significant boost to your physical capabilities, along with the ability to fly. While you might not yet have the strength to match a vampire blow for blow, you effortlessly surpass the vampire queen and king in speed. Keep in mind that when those two go all out, they are easily able to move at significant relativistic speeds, so this boost isn't meant to be taken lightly. The greatest ability of the black swan is its ability to nullify any magic it comes in contact with. Any magic that comes within an inch of any part of your body will be nullified, unlike the original which only had the arms. You’re able to form a solid anti-magic barrier around yourself and others in case you have to protect people from by magic spammers. This nullification is selective so any magic you want to be affected by will work along with your own.
The final ability of the black swan is its ability to grow in power with every generation. With each passing year you grow stronger, surpassing the past version of yourself as any limits you have are broken. Given enough time all of your abilities, powers, and everything else about you will be boosted in strength the longer you exist. Even when doing absolutely nothing you’ll find that you surpass the previous year’s version of yourself by quite a margin. If you were to train any of your skills they would gain an astronomical boost as any gains will be heavily accelerated due to your time limiter being removed. There is no limit to this either, so given a year or a short workout you’ll surpass the vampire king in strength, and will go even further beyond. While you may not be unstoppable now, time is all you need before you surpass everyone.