Katsuo(カツオ, Katsuo) is a terrifyingly tall person compared to the average human, he possesses an amount of physical strength that far surpasses the normal definition of "super human" capabilities. With his large bulk, massive speed and endurance along with his excellent combat experience he is known to be one of the most feared men within the World Government. A practitioner of the martial arts developed by the World Government, the one called Rokushiki. Having mastered all except two of the moves and even contributing to the style a technique of his own.
He currently stands as the Warden of the greatest prison the World Government has to offer, Impel Down. A prison only known to a few break-outs in its entire history of existence, still standing as one of the most dangerous places, even though its in Paradise or better known as the first half of the Grand Line. To keep prisoners in line and to protect the prison stands Katsuo, the eater of the Yōgan Yōgan no Mi and the officers of the World Government. This fruit gives him the ability to create control and be Lava himself, a fierce fruit recognized by many. His strength, and fruit ability with his ambition to defend Impel Down at all cost, has earned himself the epithet of Moeru Kabe(燃える壁, The Burning Wall)
Katsuo was born into a family of Marine officers, his father had been a Captain-Classed Marine officer, and his mother had been a nurse in a hospital next to the very same marine base his father had worked in. The marine base had been located with in the town they had lived in, so they were able to tend to Katsuo without having to leave. This town had been located along the first half of the grand line or better known as "Paradise" that is compared to the deadly New World. Since his mother had been a nurse, she had been around many sick patients, many contagious and fatally diseased. From an attack of pirates, they had decided to use biological warfare where they had introduced one of their contagious crew mates with an unknown disease to the hospital. He was quarantined and had been kept in a heavily guarded room, albeit many of the employees at the hospital were forced to be treated as well due to them catching this disease. His mother had however not caught one of these fatal diseases rather Katsuo's dad had caught an incurable disease, a highly contagious one. This had happened in one visit he had gave to his wife in which resulted in an accidental contact with the run-away patient with such disease. Katsuo's mother had reluctantly not been one of the few to catch this disease, and had all died. Unfortunately, his father's life had been claimed by the disease as well as the many unlucky ones. Katsuo had been left to take care of his family and take on his father's ambition as a marine officer.
Katsuo had been naturally gifted in combat, at the young age of 12 he was able to easily defeat normal marine officers in sparring matches. He had been promoted from chore boy onto the rank of Lieutenant Junior-Grade amongst the Commissioned Officers ranks. He had made his mother proud of his abilities, and had effectively supported himself and his mother with his pay as an officer. He had well made a reputation of himself amongst the Marine world, having become one of the youngest members of the marine with an abnormal physical strength for his age. During his training as a Commissioned Marine officer he had begun his training under the arts of Rokushiki, a practice of martial arts developed by the marines to have an upper hand in combat strength against enemies. Despite many children being trained at a young age to the arts of Rokushiki, Katsuo had been an exception to the fact that he had managed to learn many of these moves and be able to use these techniques in combat long before many of the other young ones to be able to. He was also first of these children to be able to reach a commissioned marine rank, during his training and not after.
At the age of 15, Katsuo had made a name for himself amongst the Marines for his combat abilities and had reached through the the Lieutenant rank and had made it to Captain rank. Having reached this level he had been assigned onto a different Marine base, and was forced to leave his home, to train and work on this base. Here, he had continued his Rokushiki practices, further honing his skills faster and better than most of the officers. Though these techniques had been used by the marines, most could never master every one of these abilities, which had as well been the case with Katsuo. He had never mastered Geppo, and Kami-e. These two of the six abilities had never been able to be mastered by Katsuo, which had led him to never learning the ultimate move of the Rokushiki, Rokuogan.
At the age of 18 he had ranked all the way to the position of Rear admiral, a high position among the Marines only showing how quickly he was to become stronger than many officers higher up in age dramatically. Despite just becoming an adult, he had still been seen as a prodigy, reaching the rank right below vice admiral in only such short time and had still been seen as only a child. One thing about combat though, was he had lacked experience as he had very few encounters with pirates, and had been ranked up on his pure skill alone that he had trained very hard to gain. During this age, Katsuo had a massive growth spurt, forcing him to gain a height that would dwarf an average human's height. There had been an inescapable fight that Katsuo had to do, he had fought a powerful pirate. This pirate had been an unrecognized one, and had been considered a rookie, but had much more power than the government had given him credit for. This pirate's strength had overwhelmed Katsuo, despite his incredible amount of skill the lack of experience had costed him dearly. This pirate's strength however had been short lived, as Katsuo had been losing the match, defeat had caused him to suddenly awaken his Haki. Katsuo had refused to lose one of his first actual fights with an enemy, and had begun to stress out his mind through the conflict of his arrogance and his idea of justice. He had grown angry, only to be interrupted by a strange glow that had appeared in front of Katsuo where the pirate should have been, an aura-like presence standing right in front of him. Having been able to see this, he was able to see every movement happen quite easily. He had awakened Kenbunshoku Haki first, and had caused him to continue this fight with the unknown ability. With this ability, he was able to see all of this pirate's swift attacks before they had landed, resulting in Katsuo eventually overwhelming him. He had ended the fight by crushing the skull of the pirate, ending his life and had finally said," Despicable pirate, know your place when against justice." He had hidden his discovered Haki from the rest of the government, for that he did not wish to become a vice-admiral. yet until he had perfectly honed his abilities.
After awakening Haki, he had continued his training as a Rear Admiral, only to never show such abilities directly to the government. He had continued his training and job as a Rear Admiral for ten years, only to continue honing his abilities of Haki in secret as well as mastering his Rokushiki techniques, only to never be able to master two specific ones for an unknown reason. Kami-e and Geppo had been mysteriously never learned by Katsuo, even after desperately attempting to master these skills. He had decided to do instead was to hone the abilities of his other Rokushiki, to train them to near perfection to make up for the two abilities he was never able to master. His most preferable one, and yet most skillfully used is his Tekkai, the ability to concentrate one's muscles to the point where the body's strength resembles that of iron or even stronger metals. With his natural talent to learn such abilities, he was able to use each move effortlessly of the Rokushiki, minus the two he could never learn.
With his Rokushiki training, there had been much regular physical training to the point where his bulk had slowed him down and become a nuisance, other than the sheer power he needed speed. Even Soru alone would not help despite making one's speed surpass their regular movement it did not make that far a difference. To come to the conclusion he needs to improve his speed to the point where his Soru could make a very noticeable difference to his speed he had specifically trained his legs only for some of the years of being a Rear Admiral. Having trained his speed for so long he had developed a surprisingly large amount of speed considering his height and muscle bulk, and had only grown faster with the technique of Soru.
In secret, he had honed his Haki abilities, to the point of mastering them all on his own. He had trouble controlling his Busoshoku Haki, for the fact that he did not know of it's existence until seeing a Vice-Admiral use it first hand. Having first developed his Kenbunshoku Haki, it was only natural he had trained this one first, and had made this a primary one to train until his discovery of Busoshoku Haki. At the end of the ten years of him being a rear admiral, he had fully developed his Haki abilities, as well as mastering it to the point where he could strengthen every aspect of him utilizing Haki, making him far more dangerous, with the combination of Rokushiki. At the end of his ten years as a Rear Admiral, his Haki abilities had been discovered by the World Government and had been almost forcefully promoted to Vice Admiral, albeit he did not want to be a part of the Marines any more.
Having consulted with higher-ups of the government, he had been reassigned to a different branch within the World Government. He had been assigned as the new vice warden of Impel down, the most dangerous prison of all of the World Government despite being in Paradise. This had been just where Katsuo had wanted to work, he had wanted to keep all criminals behind bars and if not, death. This had also been a useful way for Katsuo to hone his abilities in peace, without the distractions of the Marines sending him to hunt Pirates and such. From then on, Katsuo had pledged to never let one to escape this prison and to squander its name again, after finding out about it's history from one of the elders who had worked among the government. During his time as a Vice-Warden he had come to invent the technique Shiōha, a move to replace his lack of Rokushiki that had taken him a long while to fully use the power of the technique he had created.
He had obtained a devil fruit that had been found on one of the prison ships docked on Impel Down. This fruit had been apparently confiscated from a pirate ship, and made its way to this ship. He had known what it was and the potential danger of eating one could have catastrophic effects. Curiosity had taken over Katsuo, he had wanted to know what the ability was and he had eaten this fruit to find out its power. The risks of it being a useless fruit could have been quite great, one to ruin his reputation as a member of the World Government. This had not been the case, he had eaten one of the most rarest kinds of fruits, a Logia fruit, or more specifically the Yōgan Yōgan no Mi, the ability to control and create lava in a mere whim. This had been an incredibly dangerous fruit, allowing him to scorch and incinerate any of those who had stood in his ways with the addition of his already mastered physical abilities made him nearly unstoppable.
With this massive ability of destruction, the World Government had recognized him as one of the more deadlier members of it. They had ranked him up to the level of Warden of Impel Down with the knowledge of his powers would make it unlikely for any one to ever escape such a prison. His lava abilities would burn any escapees, and would use it as a torture devise to prisoners who did not abide to his law within the prison, he had soon grown overwhelmed with his power. He had grown to hate the members within the prison and had burned slightly when ever he had grown annoyed.
AppearanceEditHis height is quite enormous for a human, as it towers over the average height of humans. He is known for his height, and adds an extra level of fear to his opponents because of this height. He had a massive growth spurt right after he had quit the marines to join the ranks within Impel Down. He had went from 5'6" to 11'8" within a few short months during this age, for an unknown reason other than luck itself. He is a very bulky person, but with that bulkiness he had trained himself to the point where he can even keep up with his speed with the bulk of muscle. This bulkiness only compliments his massive height, showing that his pure power and endurance are his main skill points just by seeing him.
Given his natural appearance, he could easily be seen as a dangerous, serious and a hateful man which had been the case many times. This is actually mistaken, he is actually quite an easy going person when not around other pirates or criminals. When he speaks with people on an equal level, he often speaks very informally in a quite relaxed tone. He would offer a drink to those who had been acquainted with him at the time. The drink though, usually melts due to Katsuo usually enjoying hot beverages and often burns who ever drinks it unknowingly. He can at times be seen as an eccentric guy given his hobby. He refuses to approach anyone in a dangerous manner even if they get quite annoying he can easily deal with, except his behavior when around criminals.
When around criminals he tries his best to keep up his obvious tough guy attitude while threatening ones who speak out of turn. He also uses rounds of occasional torture to scare the prisoners by giving one unlucky criminal burn wounds from his lava abilities. This method is quite effective in keeping less dangerous criminals in order and usually shuts them up when he threatens to burn another prisoner. This is not the case however for more dangerous criminals on the lower levels, they refuse to be intimidated only leaving Katsuo to further torture and often kill off some prisoners when taking things too far. Given this method of occasional torture, he has proven himself to be an effective Warden within the prison. He is a very friendly one when another is a law abiding person, to a criminal he is their worst nightmare.
Despite having lost a family member from a young age, he had learned to cope with such depression and the stress of having to support his family. He had learned to cope with it quickly, only showing how he is able to control his emotions when he needs to. Since he is able to control his emotions, he is able to keep them from clouding his judgement, where he believes his judgement is absolute within this prison. He swears to keep the prison in line no matter what, even if his mother had happened to be in Impel Down he would not let his emotions ahead.
Katsuo personally enjoys making flashy entrances be it whether it is to a friend of his, a stranger or an enemy. He loves having seen people's reactions to such flashy entrances and had learned to use his lava fruit to only further his flashiness. He is followed by two of the same officers within the prison carrying transponder snails that emit catchy music. The two officers names are Mark and Cody. They often follow him around as students that he trains, but are required when he is about to make a flashy entrance or he'd get pretty mad at them. He has been known to have a hobby of making different kinds of flashy entrances, which all weirdly all have the same music playing.
Having an outstanding amount of physical strength had made him most reputable for, he was able to do feats with his strength no ordinary person is able to. Along with his height, comes a large bulk of muscle making him seem incredibly powerful. Able to create regular shock-waves with his strength due to sheer force allows him to only demonstrate further his power. With such power Katsuo is able to punch through the walls of the inside of Impel Down and had almost accidentally killed some of his prisoners through punishment methods when he was not using his devil fruit ability. Along with this enormous amount of physical strength, it increases his ability to accomplish techniques preformed by Rokushiki. Such as Tekkai(鉄塊, Iron Body) makes him near impenetrable due to his sheer amount of power, with his large bulk it provides an increased amount of protection when using this technique.
His greatest skill, is his endurance, being able to endure many slashes to bullet wounds and to being pummeled into the ground countless times. He is most known for his incredible durability, having survived days worth of break-less training sessions in his younger days had only morphed his stamina to what it is to this day. His brute physical strength can only contribute to his natural endurance, making him able to withstand many things, and survive the deadliness of even being cut down by a blade to only keep standing back up. The greatest contribution to his title Moeru Kabe(燃える壁, The Burning Wall) had been his insane amount of stamina.
His endurance had saved him on many situations, with one being fights with Pirates. During his fight with an unnamed powerful pirate, in which he had awakened his Kenbunshoku Haki, his endurance had been the thing letting him keep standing up after countless times falling to the ground. Being punched in fatal spots which would have killed any ordinary marine soldiers, had only ended up in Katsuo keep standing up high to the point where he had faced almost certain death. This had pushed him to the limit and had sparked his awakening of Kenbunshoku Haki, only because of his determined stamina.
His stamina is only amplified when used in conjunction with Tekkai, allowing for him to resist techniques as well as being able to take them as he is regularly. It only makes sense that Tekkai is his favorite move to use defensively and uses it more than he does the other Rokushiki techniques. His mastery over Tekkai with his natural endurance makes him nearly impenetrable, and incredibly difficult to take down in the midst of combat. As his last resort form of Tekkai, which is his strongest technique of Tekkai is to completely cover his body in Busoshoku Haki hardening with Tekkai to completely make himself guarded.
Tekkai(鉄塊, Iron Mass): One of Katsuo's strongest point in his Rokushiki practice, allowing for him to tense up his muscles to the point where it can match the toughness of the strongest of metals. Like its name, it allows the user to concentrate their body to resemble iron itself, despite the body being of flesh and muscle. Along with being able to defend from devastating attacks while preforming this technique, it is also able to strengthen one's attacks because of the muscles intensifying at the point of attack, therefore increasing the power of one's offensive capabilities. Katsuo has proven his capabilities using this technique to easily block the slashes of several pirate henchman's swords simultaneously to the point where they had all broken their blade off of him. Katsuo had shown to have no injuries as a result of these attacks, while this had still been during his time in the Marines and before he had joined the ranks among the prison known as Impel Down. Even against advanced swordsmen, he is able to escape heavy injury by using this technique to receive minimal damage, depending on his opponent though. Ever since he had obtained his Logia fruit he had never seen a need to use this ability as no one would be able to hit him without having to use Busoshoku Haki. He still trains his abilities in his free time, especially with this technique which had made his first priority, to further hone his ability to use Tekkai. Since he did eat his devil fruit, even Haki users will be burned when attacking him, and when using Tekkai will provide for an offensive gain as well as a defensive gain.
- Tekkai no kōka(鉄塊の硬化, Iron Mass Hardening): To strengthen the defensive properties of Tekkai, Katsuo is able to cover his entire or parts of his body in Busoshoku Haki to completely strengthen his defense. This would allow him to combine the effects of concentrating the muscles while obtaining the concentrated black metal-like substance created by his Haki to the point where he would be near impenetrable. This move can also be used to cover parts of the body as well when using Tekkai, allowing for protection in important areas to save his energy and not waste his strength. This technique is known has his strongest defensive technique using Tekkai and Haki simultaneously, and is only used to completely block potential incredibly powerful attacks that seem inescapable.
- Tekkai "Utsugi"(鉄塊「空木」 Tekkai "Utsugi", 'Deutzia'"): This move is commonly referred to Katsuo when using this as Iron Body Empty Tree when preforming this move, tradition passed down from previous users of this technique. The art of using one's defensive technique to preform an offensive counter-measure. While one strikes the user of this technique, it will have a different effect than the other Tekkai uses. While the normal Tekkai technique has one absorb such a technique, this one is meant to cause something similar to a counter attack. The force of the attack causes a shock wave back onto the opponent causing large amount of damage back to them. This move can result in broken bones for the one attacking this form, and quite obviously depends on the force the enemy attacks.
- Tekkai Shisei(鉄塊姿勢, Iron Mass Stance): A controlled use of muscle concentration of Tekkai, limiting to one half of the body. When using Tekkai in the upper half of the body it allows for one to strengthen their upper body attacks while still being able to move with their feet. The reason Katsuo is not able to completely use Tekkai and move while in it is because of the amount of muscle being concentrated would not allow movement without releasing much of the protection offered by the technique. When using Tekkai in the lower body only, would only have to be used to keep one's balance while having to fight using the upper body only, which would prove ineffective unless the situation had shown itself where it was needed.
Shigan(指銃, Finger Gun): A move used by Katsuo in close combat, which is sometimes usually never the case, as he is able to keep his distance in most of a battle using his deadly devil fruit ability. This move is usually used as a fully offensive attack, albeit it can be used to counter blades when used rapidly when it is imbued with Haki's black metal-like material. When infused with this, his attacks pierce more easier and even similar to that of a bullet, only to surpass a simple bullet in power. During his training to develop his understanding of this technique, he had broken his finger many a time. Albeit he was talented in pure natural abilities, he had the same trouble as any ordinary person when coming to master this technique of Rokushiki. Using his devil fruit, each of these finger pistols upon making full contact with the enemy, burns them as well as piercing them which inflicts farther pain and damage to them, with the high chance of burning their internal organs if pierced right through the body for enough for the heat to enter.
- Tobu Shigan Madara(飛ぶ指銃斑, Flying Finger Gun Spots): An advanced use of Finger gun, allowing for short range combat as well as long range combat, which is especially useful for that each attack from these pierce sharper than a bullet and fires more rapidly and faster than one. Much like the regular Finger Gun Spots technique, it utilizes the index fingers in both hands to fire finger guns rapidly at high speeds. Using the power of the force of the flying finger gun attack to strike small long range piercing attacks that strike more deadlier than an actual bullet from a gun.
- Shigan Akumu(指銃悪夢, Finger Gun Nightmare): A fairly simple version of his finger gun technique, but is only used when pinpointed onto one specific spot. This move aims specifically to poke the butt of the user, resulting in likely their death. This move is ineffective and unrealistically do-able in actual combat, more or less an execution technique to instantly finish someone off.
Rankyaku(嵐脚, Storm Leg): Much like the shigan, this move is capable of piercing targets and even strong metals such as iron can be pierced using this technique. Utilizing one's leg movement and strength they are able to send compressed air blades with only the movement of a limb, most preferably the legs. Given Katsuo's larger physique his Rankyaku's are much larger than that of a normal Rokushiki user, making his much more lethal and able to cover farther ranges, and able to deal much farther damage due to his physical strength. He uses this move rather more than he does the Shigan technique as it is quite deadly and fits his deadly nature very much to be able to cut targets and even cut them directly in half with ease if it directly. He is able to imbue this technique with Haki which forms a much darker air blade, with this increased amount of force the Rankyaku is just far more dangerous than it was previous to infusing it with Haki, allowing for as well as piercing Logia' and Paramecium users that could block pain with their form of body. He had learned to utilize his devil fruit to increase the damage of these compressed air blades created by the swing of the blade by increasing the heat of the air in these compressed air blades to the point where they would burn upon contact as it pierces as well. Once infused with Haki and incredibly heated by his lava's temperature this move takes a red-black color when it launches as an air blade. This had been the second move Katsuo had mastered of the Rokushiki techniques with the first being the basis of them all, Soru. Albeit Tekkai is his Favorite to use Defensively, Rankyaku is his favorite offensive technique to use as it provides for long range attacks when he is not using his devil fruit.Soru(剃, Shave): The fundamental technique for learning the martial arts basis of Rokushiki, the Soru technique is one needed to learn to master these abilities. Often when learning Rokushiki, this technique happens to be the very first to be taught to students for the obvious reason that it is needed to open the gateway to all other skills. This move takes control of one's muscle control as well as their control over their legs to be able to produce these incredibly speed bursts. This move allows one to excel normal movement onto a whole new playing field with extremely high movement, almost as if someone disappeared and reappeared from thin air to the untrained eye or non Haki user. This move had been not so effective for Katsuo to use when he had first gone through his growth spurt as he was majorly slowed down, and did not have enough lower body strength to completely support the full movement bursts of Soru. As he trained his lower body during his time in the marines and even as he spent his time in Impel down, he had increased his lower body strength to the point where he could not only move naturally faster, but using the kicking method of Soru to kick ten times on the ground in one burst could be used easily by Katsuo. This had allowed him to move fast despite his large size, and bulk to a degree where he could dodge moves, but as well keep up and out maneuver untrained Soru users. Despite other users of incredible speeds that compare to Soru, they often cannot keep up with their own because they did not undergo the same amount of training one who had to learn this technique had gone through, as Katsuo is able to easily keep up with his own speed it means he is able to simultaneously fight while using Soru.
Shiōha(四王波, Four King Wave): A move similar to that of Rokuogan. A technique that requires all six of the Rokushiki techniques to have been mastered for one to ever have hoped to learn Rokuogan. The principles behind the technique of Rokuogan is to have combined each of the techniques of the Rokushiki into one powerful move. Katsuo had mastered every single one of the Rokushiki technique with the exception of Geppo and Kami-e, allowing for him to never truly master Rokuogan. Rankyaku contributes to the long range capabilities of the blast created by Rokuogan. Shigan allows for it to fully pierce through the enemy, sending such shockwave through the opponent rather a concussive force. Tekkai allows for one to tighten the muscles in the arm for to increase the amount of force summoned upon by Rokuogan. Soru, the fundamental move for one to master Rokushiki, as well as requirement needed for to supply the force needed to activate Rokuogan. Geppo and Kami-e, the techniques required for one to fully understand the necessary control and precision needed by the Rokuogan, these two techniques had not been mastered by Katsuo allowing for him to never have the control necessary for Rokuogan. He had created a move similar to that of Rokuogan, one that uses the moves that Katsuo currently understands, one that does not use as much control or power as a fully mastered Rokuogan technique. This technique fires a shock-wave similar to that of the Rokuogan, one that can pierce an enemy but does not have a precise strike as it literally blasts outwards, instead of straight. Since it fires outwards, it would be powerful at close range, but not necessarily dangerous at long range, which as well allows for one to crush their enemy's internal organs similar to that of Rokuogan. This move does not emit as much raw strength as a Rokuogan either, but its power is made up when Katsuo had learned how to increase the temperature of this technique, allowing for Katsuo to burn one's insides once the technique pierces them. It's temperature increases due to his devil fruit's ability to create lava which has a devastatingly high temperature to increase the temperature of this wave. With this increased temperature, this technique takes a red-like color. As with this technique being further strengthened by one's Haki being imbued to this power, makes up for the loss of power of not fully learning the Rokushiki, as Haki will immensely improve the power brought by this technique, as well as giving this attack a black-like color as well. As the end product of this technique will take a black-red color.
Having mastered Haki in secret had made training for understanding this Haki especially difficult. Since he had awakened Kenbunshoku Haki first, he had little to no way of realizing there were even a second form of Haki, one to be able to control an invisible force produced entirely by oneself. He had first discovered this Haki when he had seen it firsthand, which had made him fully aware of this second form of Haki, allowing him to have a general understanding of what to aim for. Since he had no one else to train him, he was forced to train himself which had made his self-training take longer than it should have if he had been with a well teacher. Taking several years for him to fully develop this Haki, after he had trained his Kenbunshoku Haki he had understood the capabilities of such strength.
When concentrated enough it forms a black metal-like substance to form on the body composed of this power only to strengthen one's body even further. Using this form of Haki allows him for to attack opponents with a noticeable amount of increased force. Such force able to make the difference of slight crater in the wall, to a large hole in a iron sheet. To Katsuo's already incredible physical strength, this would make a very noticeable upgrade in pure power when imbued with Haki. With Haki, his pure power is enough to create devastating amounts of damage with only his raw strength. Using his Haki he is able to strengthen his Rokushiki techniques to further his strength among his martial arts capabilities with this style developed by the World Government. He is able to make Tekkai endure more damage when using the concentrated black metal-like substance of Busoshoku Haki, allows to make Tekkai far more stronger. To enhance Shigan, it allows for him to pierce the opponent much easier, and provide for much stronger force, which is the same case for that of Rankyaku. The power of Shiōha, is also strengthened by the use of this form of Haki.
The Yōgan Yōgan no Mi is the fruit that had been consumed by Katsuo. This fruit allows for complete control of Lava, to create it at will and to be lava themselves. This fruit is classified as a Logia, one that makes the actual person them self into the given element, which in this case, Lava. A deadly fruit sought out by many only to be eaten by the current Warden of Impel Down, one of the most useful abilities for keeping prisoners in line as a way of torture and killing attempted escapees. Having first found it on one of the prisoner ships surrounding Impel down, he had generally taken it without permission, but no one had seemingly cared.
He had trained over his mastery of this fruit during the three years he has been a warden so far, allowing for quite some time to learn how to use it. Although it was only three years of learning how to use this fruit, he is fully aware of how to control it at will, but has not learned its fullest capabilities. From his past experiences, he has thought of uses for his lava that could help in certain situations, and had made some unique ways of using this fruit. The power of this fruit is quite devastating and can only bring destruction within it's path. Capable of burning whole towns with enough spread of lava, and killing most people once in contact due to the immense amount of heat. Also able to entrap gases as well as to release such gases in a form that he is fully able to manipulate and separate from his lava that would normally knock out, if not suffocate a regular person.
Katsuo is immune to the effects of lava for the pure reason is that he is able to be lava itself, allowing for him to be immune to the gases it releases as well since it is technically created by the lava. Having that said this means he is also able to resist immense heats, unless of course the heat surpasses that of even lava itself. In fact, Katsuo prefers to be in quite hot areas for his time meaning his favorite area to stay in would be Level Four Blazing Hell of Impel down due to the extreme heat in the air makes it quite comfortable for him.
With his ability to control lava that he's able to form, he is also able to control outside lava created by nature or some kind of other source. That having been said, that means the fourth level of Impel Down would be the most ideal place for him to fight one due to the amount of lava placed within it to keep the room heated. This would practically give him an ultimate advantage in and almost unbeatable once encountered within this floor. It's also Katsuo's job to make sure that level four does not ever cool off ever, so he regularly supplies it with lava everyday using his own devil fruit power.
His ability to create lava lets him be able to further pressure it, which would directly cause the temperature to rise as a result.He can take this method a step further by forcing the compression of his Busoshoku Haki as well into this pressured lava to form a quite literal form of solid plasma, much hotter than regular lava and is in solid, changeable shapes. These shapes can range from small ball-like projectile to being even a hammer. This would normally burn Katsuo due to the heat being higher than that of lava, however having trained his devil fruit abilities, he has learned the ability to manage higher heats and quite literally even change his body into this higher state. Though, since this ability requires a lot of pressure it would force Katsuo in a smaller child-like size, while maintaining his regular physical prowess. This child-like state lasts about a minute after Katsuo is finished using it on his own until he resizes his body back to it's regular shape with his Logia ability.
- Shakunetsu Hakai(灼熱破壊, Burning Destruction): A basic technique of this fruit has the user cover their arms in lava enough to be launched at someone with a considerable amount of size. This is done quickly due to the user being composed of lava allowing for continuous launches of the devastating destruction of lava. When used in the Impel Down building Katsuo launches this technique side-ways towards the potential opponent or crowd to literally take them all out. When used potentially out doors, Katsuo would launch the lava in the air as if a volcano erupting so that it would crash down from the sky randomly taking out anyone in the path, cooling off slowly in water to create hard large chunks of rock. When the lava lands and is not cooled off, it released fumes of deadly gas capable of knocking out someone when inhaled. These attacks are capable of fatal damage upon impact thus burning the victim alive until death or if they had somehow escaped this technique they would leave with serious amount of scars due to the amount of heat generated from the lava.
- Nenshō-ha(燃焼波, Burning Wave): Summoning a colossal amount of lava at the user, and is launches as one incredible wave of burning lava, destroying everything in its path. This move is used as one to finish off his opponent quickly, and is quite effective within Impel Down as since it is indoors the lava will consume everything in it's path leaving behind noxious fumes and searing flames. The destruction compared to the possible damage to that of a town would be quite major, being able to take out much of a town in one massive wave and eventually the entire area once given enough time and lava supplied to it. Using this move at an island-range can literally change the climate of an island with only the time of a few days, when being supplied continuously. The height of his full burning wave easily dwarfs even that of a Pacifista, only adding to the incredible amount of danger supplied by such a technique.
- Nenshō Shadanki(燃焼遮断器, Burning Breaker): The same start as the Burning Destruction technique, involving the arms being coated in a large amount of pure lava, without having to be launched. Instead, he uses these largely coated arms as to use for attacks which provide for longer range and can practically incinerate what ever it makes contact with. Melting iron itself, as well as searing through the human body with ease with only the need of one direct attack. This would weaken the opponent when fighting close range against this as the lava already releases a noxious fume, so at close range it would only weaken them. When this move causes the opponent to move to a long range position, it can then be launched as if his Burning Destruction technique. This attack as with his Burning Destruction technique can be imbued with the invisible force of Haki, allowing it to block attacks as well as pierce Logia' and cause overall much more destruction.
- Ravu~agādian(ラヴァガーディアン, Lava Guardian): Using Katsuo's full control over the Lava element while being able to produce it, he shifts the lava into a large figure. Using the enormous amount of lava he can easily produce he can form this in short of a minute by moving his lava to create a large monster-like entity. This creature is often as large as Katsuo's Burning Wave technique but can have it's size adjusted depending on one's environmental circumstances. This entity is mobile and can reform unless the user of this technique loses complete focus of this technique, this move however can be cut down with a stronger force of Haki than the amount imbued onto the creature. This monster attacks the enemy with it's incredibly hot body, burning everything in it's path with brute force as Katsuo is still able to fight. The creature is also able to blast small bits of lava bursts at the opponent, but only to a degree of a smaller size and moves some-what slowly. Despite it's lack of speed it is quite powerful and dangerous, capable of burning even swords like regular lava because the creature is made of lava. As well as regular lava, this creature emits a noxious fume capable of weakening and knocking out one's within it's range. This technique is as well reinforced with Haki to be able to defend temporarily against Haki users, with its elemental weakness being water.
Katsuo's Finger gun nightmare is based off of Oda's reply to a fan question stating that if someone got poked in the butt with Shigan they would die.
This character is based off of Hiko Seijūrō XIII from the Rurouni Kenshin anime series, but holds little to no relation to Masamune, another character of this author using character pictures from the same series.