Bloodcurdle allows Chizome to temporarily paralyze an opponent by ingesting samples of their blood.
Chizome only requires his tongue to make contact with a small amount of a person's blood, regardless of where and how it's found (for example, coagulated bloodstains on a curative). Once the user gains access to his target's blood, they can activate Bloodcurdle and immobilize their target for a limited period of time, leaving them vulnerable to a finishing move.
The amount of time a victim remains paralyzed depends on their blood type in relation to the user's own. In Chizome's case, blood type B represents the longest amount of time, then decreasing to AB, A and finally O for the shortest amount of time. Enemy blood types can vary widely and Chizome has no way to actually identify them, meaning the timing of each paralysis can become unpredictable. Regardless, the maximum amount of time anyone can stay paralyzed for is 8 minutes.
The Hero Killer made a name for himself by infamously paralyzing Pro Heroes by collecting their blood from the weapons he skewered them with. Stain targeted Heroes one-on-one, ambushing them in dark and narrow alleys in order to score first blood without attracting attention, giving him an opportunity to activate his power unimpeded.
His arsenal includes various swords and knives that become stained with blood after slicing through their target. Stain then activates his Quirk by licking the blood directly from the blade. As a very capable villain, Stain's battle prowess allows him to overwhelm his targets in armed combat and compensate for his Quirk's restrictive activation cost.
Back in his vigilante days, Chizome would collect bloody, used curatives discarded by criminals as a way to acquire their blood, using those as an easy way to instantly paralyze said criminals through Bloodcurdle.
- Blood - Wikipedia article about the substance Chizome's Quirk revolves around.
- Blood type - Wikipedia article about the blood classification that influences Chizome's Quirk.
- Paralysis - Wikipedia article about the main effect of this Quirk.