"Compared to the hellhole we Hollow call "Hueco Mundo", death might be a more kinder place for you. So relax...this will only take a moment."
Acciaio has dark skin, black hair, and purple eyes. His clothing is composed of black and gray armor, arm guards, a strange tattoo on his left shoulder, and black pants. His own reason for wearing this type of uniform is so that he can fight with less hinderance as possible.
Acciaio is considered, even by the Los Cinco Dios, as one of the most feared Espada in the generation. He is mostly calm and level-headed, but can be easily bored, and even more ill-tempered. Despite his awareness of his Eximo Espada leader's ranks, he will use mockery, brute force and coercion on them in the belief that they are doing something extremely "foolish". This has led him to several confrontations with Odio Soltar, and several times their teammates have had to forcefully restrain the both of them from attacking each other.
Another set of fearsome traits is his love of battle, sadism and lack of mercy shown on an opponent. Unlike most members of the Eximo Espada, he enjoys to use physical and mental torture on his opponents for his own amusement. His fighting styles involve inflicting the most pain on his opponent without killing them, even forcing them to the brink of insanity.
Blanco Viento even once wondered why he was not even in the Los Cinco Dios, much less a low-ranking one.
Acciaio's abilities continue to mark his place in the Eximo Espada as a phenomenon even more. He displays a proficient level of experience in battle, as well as an immense amount of strength and skill. It was even said that his power could rival the current Dios Segunda Espada's, although this has never been proven.
Master Swordsmanship Specialist: Acciaio's swordsmanship skills are at master level, having both a combination of elegant and aggressive movements. His cutting strength outrivals that of Odio's, as such in a battle against Ryan, when he sliced the latter's sword down to the hilt.
Master Hand-To-Hand Combat: Acciaio excels even more so in his abilities in close quarters combat than anything else. With quick speed, power, he is able to quickly disable, disarm, or even kill an opponent with a simple combination of grapples, punches, and kicks.
Vast Spiritual Power: Even to the Los Cinco Dios, Acciaio has great spiritual power. His spiritual pressure reaches to the point where an enemy's physical or projectile attack can be repelled by focusing it, or sometimes even paralyzing the opponent out of sheer terror.
Keen Intelligence: Despite his appearances, Acciaio is a very perceptive and smart fighter, able to pick up on things he had not even the slightest experience with. He is also understanding of people's emotions by their thoughts and actions, which allows him to toy with his opponent's emotions. For example, he singled Bella out as "a person who's afraid to let one of her comrades die".
Enhanced Strength: Despite his build, Acciaio has a large degree of strength, and has displayed this several times without hesitation, either by his cutting strength or his ability to catch heavy weapons one-handed.
Sonido: By his own claim Acciaio is very fast in terms of Sonido. However, this has yet to be proven.
Cero: Like other Hollow, Acciaio is able to use Cero. However, he is rarely seen using it.
Gran Rey Cero: So far, Acciaio is the only Eximo Espada to have presented to use the Gran Rey Cero, despite the other Espada being able to use it as well. It has a black-gray color.