My polarity is only usable when I have enough aura at my disposal. It's not magic, per se, but.... It's kind of like chakra, you know, but.. If my aura gets too low, my semblance will cease to work, and if I attempt to use it while my aura is at its lowest, it'll weaken me to the point of near death. I am able to perfectly control my semblance and aura output so that I don't face that problem, so I'm always at full aura. My aura is also a shield, it allows me to take lethal blows without damaging me much, but sneak attacks or my clumsiness are not affected by my aura shield. I think that's about it....
