Mercury Black is a gray-haired associate of Cinder's who uses a pair of greaves that also function as guns. Mercury is shown to be rather care-free and jokes around when in the company of Emerald, whom he makes an effort to annoy. He sees to opt for excitement and action, however, when it comes to matters at hand, Mercury drops this attitude, focusing himself on the mission. During battle, Mercury displays a sense of seriousness and levelheadedness. Based on his fight with Pyrrha Nikos, he appears to test and gauge his opponent before fully committing to an attack, implying that he has a strategic mind. Judging from the nonchalant way he talked about killing Tukson, Mercury appears to have no qualms about killing, even light-heartedly joking about it afterwards with Emerald.
Powers and Stats
Tier: At least 8-A
Name: Mercury Black
Age: Around his 20´s
Powers and Abilities: Superhuman Physical Characteristics, Expert martial artist (resembles Tae Kwon Do), can adapt to his opponent´s fighting style, Able to manipulate and use his Aura (Ki/Chi) defensively (Enhances his natural durability), offensively (Enhances his striking power and sharpens his senses), and to unlock the Aura of another person, Skilled marksman
Striking Strength: At least Multi-City Block Class
Range: Standard melee range, dozens of meters with ranged attacks
Standard Equipment: Greaves, Prosthetic Legs
Intelligence: High (Mercury appears to be highly observant of his opponents and can easily analyze their powers and fighting styles by sparring with them once)
Weaknesses: Cocky, continual use of his Aura will cause it to decay to the point where he can be left weakened or even incapacitated
- Mercury's Boots - Mercury Black's weapons of choice which he uses in tandem with an acrobatic fighting style, emphasizing kicks in combination with his greaves. Mercury's weapon appears to be a large pair of greaves with a firing mechanism built into them, similar to Yang Xiao Long's Ember Celica. They are shown to be able to fire a variety of different projectiles. Some of the projectiles are shown to have guided or target-seeking properties, taking spiraling paths towards their target. By using a fighting style akin to breakdancing or Capoeira, Mercury can fire a veritable storm of these projectiles that can overwhelm an enemy with sheer volume. Some projectiles also appear to create a smoke or steam effect that can be used to distract enemies. He can also use the boots to jump in midair by bringing his legs together and firing his boots simultaneously, boosting him forward and allowing him to achieve temporary flight. This is likely a reference to the Roman god Mercury, known for his speed and ability to fly with his winged sandals.
- Dust - Mercury can also control the rounds through Dust use. During his tournament fight, he gathered multiple rounds that spun around him in a manner similar to that of a cyclone surrounding him before the rounds were later unleashed in a devastating flurry. He also possesses marksmanship skills, being able to fire his Dust rounds efficiently despite the barrels being located at the soles of his boots, as shown when he fired a round at Yang before using his cyclone technique during their fight and when he shot Ruby's Scroll out of her hands during their confrontation.
- Prosthetic Legs - Mercury has a pair of robotic legs which he acquired at some currently unknown point in time. His prosthetics make-up over most of his leg, including a portion of his thigh and everything below the knee. He usually keeps them concealed under his pants. These robotic legs appear to give him enhanced performance in battle, such as being able to withstand blasts of fire without taking damage. This is most likely why he was able to withstand Yatsuhashi Daichi's strong hit from his weapon during their match and easily recovered. He is also able to very easily repair "injuries" to his legs that would otherwise put a normal human out of commission or require medical attention. His kick-based fighting style, as well as his choice of weapon, are likely intended to take advantage of his prosthetic legs. His prosthetics are capable of firing blasts of air, which he makes great use of in combat.