Riki X. Wilson also known as simply "X" is a skilled assassin apart of the Cipher Pol. At one point in his life, Riki was affiliated with the Marines where he picked up useful skills like Rokushiki. Although young, Riki came into the Marines with an array of combat abilities that even trumped some officers. Riki's prior skill enabled him to quickly learn the combative skills of the marines and master them afterwards.
As a member of the Cipher Pol and a highly skilled assassin Riki's personality is compared to that of a robot. Riki is as ruthless as ruthless can be. He's not compassionate for anyone or anything whatsoever in that world, not even himself. His reasoning is that "Everything can be replaced" that even applies to himself. He considers himself as a highly skilled individual with skills that are somewhat unique to himself however when he dies he will simply be replaced by someone with capabilities similar to his own that maybe even a better assassin then himself. This system of replacement is present in the world today with the government replacing officials like admirals and even in the pirate side of the world like Yonko. Riki was not always like this. Before joining the Cipher Pol he had compassion for other people, putting other people before himself. It was how he was raised when he was back on Fishman Island even when he was a slave and protector to the nobles he was with. He was always selfless in his actions and it wasn't until joining the Cipher Pol that his compassion did a complete turn around for the worst. When encountering old friends and enemies that knew him before the Cipher Pol they always ask him what happened.
Whenever he is on a mission to assassinate a target, goes into the mission we no regrets no mater what will happen. With that being said killing women, children, or elderly people is no thought to Riki at all. If it gets him to his target then he will do it. This ruthlessness and attitude towards his missions are part of what propelled him though his years of training as a Cipher Pol agent.
Riki must keep his skills as an assassin at a peak at all times which is why he trains almost all the time and seeks out new power all the time. Every opportunity he comes across to learn something new that could potentially increase his ability as an assassin he does not hesitate to peruse it. What is amazing is that Riki is hands on with many new skills he seeks to learn, he will spend years to master a skill if need be. This just isn't in terms of physical capabilities like learning a new fighting style, in general the more knowledge he has the better adapt he is to the world and its ever changing cycles.
Another interesting thing about Riki is that he does not smile at all. He hasn't smiled in years not even cracked the smallest smirk even when fighting someone that pushes a fighter like himself the thrill does not make him smile. It is the same blank looking expression at all times for Riki. Somehow this expression works during infiltration and disguise missions. To make up for this Riki can be a very talkative person and very persuasive with his words. This trait is another factor that makes him such a great assassin because if he can get the ear of one person then he can get the ear of twelve people. Being persuasive, Riki has a cunning and quick tongue that often gets people to react to what is said by Riki. Usually when he says something that offends someone it is to evoke a reaction from them whether it be physical or informational. As an assassin he cannot react to something like an insult or be provoked by an action from a person especially one that is essential to a mission because this can completely blow both his cover and the mission. Riki is extraordinarily calm during situations that could cause mass panic, keeping his focus on the mission he was assigned to.
Riki has an array of abilities in his arsenal. Being primarily an assassin most of his technique especially his Fishman Karate techniques are centered around precision and accuracy. The ability to take out a person quick and effortless without collateral damage instead of having abilities that cause mass destruction. That isn't to say Riki doesn't have abilities that cause mass destruction because every once in a while he encounters multiple opponents or has to cause mass destruction which is where his Fishman Jujutsu comes into play. Riki also relies on his intelligence and knowledge of his opponent before a battle. Riki doesn't fight fair whatsoever, he will exploit weaknesses until eventually he wins. Holding back ins't something Riki does often during fight either, the norm for many battles is to hold the trump car for last while that is the case for Riki many people build up to that trump card. Riki attacks to kill and if that means using his strongest technique in the beginning of a battle he will do so in order to gain the advantage.
Riki learned in the Cipher Pol how to fight with anything at his disposal including a weapon like a gun or sword. Before he could become an assassin he had to learn a basic use of many weapons. However Riki decided to become more than just a basic user of weapons and instead decided to train with hundreds of weapons until he was average with them ensuring that just in case he went toe to toe with someone and was using a weapon he could suffice in a battle against an enemy.
As a Fishman, Riki was naturally born ten times stronger than a human. Riki maintained that strength through to its current level now. Through training he has increased his strength to be even more ten times the strength of a human. His natural strength difference over humans it what aided him with mastering most of his Rokushiki technique's and become a member of the Cipher Pol so quickly. Although his is more than ten times stronger than humans, Riki's brute strength isn't displayed that often at it's fullest potential unless he is up against someone with monstrous strength and abilities. Being an assassin most of his physical training went into technique rather than brute force. At any time Riki can display his brute force he instead contains his strength to a specific area when attacking. He has enough strength to quickly dispatch a powerful foe in a single strike. To compliment his strength Riki has extraordinary speed. Riki is so fast that his attacks can outpace the reaction of an average Kenbunshoku Haki user. This speed advantage Riki holds against most opponents separates him from many of his peers. Quickly being able to attack before the opponents reacts is how many of Riki's battle start and end. Riki's motto when attacking is; "Attack quick and hard so you only have to do it once."
Riki also has an ability that is naturally apart of his body due to his Fishman dna. Riki has an unknown ability that allows his body to passively send out unsensible and invisible electromagnetic waves which tells Riki whats around him. These waves a released thousands of times ever minute which makes it almost impossible for someone to bypass them unless the person is enhanced by a devil fruit. Riki can lose all of his senses and still be able to sense whats around him. Riki has had this ability since he was born however didn't realize the full extent of it until his adult years. This ability allows Riki to react to anything coming his way, consistently if something outpaces his Kenbunshoku Haki this can make up for it.
Riki's intelligence is his strongest weapon. Before going into any situation if he can he always does research prior to that situation. Give Riki a day to study a situation and he is virtually unstoppable unless that situation is exceedingly complicated. Even during the midst of a battle Riki analysis his opponent and acts accordingly to the information he has. Riki has been through thousands of training scenarios and even more actual situations that were completely different from training scenario. His experience expecting the unexpected accommodating the situation that of veteran Cipher Pol agent.
His intelligence has been displayed since a child being able to quickly learn Fishman Karate and Jujutsu and master if years after learning the concept behind it. His knowledge of other things like history, science, nature, all equate to how he handles situations. His battle expertise is surprising to many because of how young he is. Riki gets the full scope of a situation and quickly devises a plan on how to attack that situation. Using anything to his advantage is what separates Riki from any other average assassin. Against devil fruit users especially needing an advantage is required depending on the certain fruit and its power. Knowing his own capabilities is also how he gauges how to attack situations. If a enemy long range fighter Riki knows his long range abilities aren't able to match up unless in or near a body of water. So he will attempt to close the distance and engage in a close range battle. If an enemy is a great swordsman he knows to stay agile because most sword attacks are linear and dominate in close range battles.
Riki studied the human anatomy while training to become a Cipher Pol agent. He learned where on the body to aim to inflict the most damage or cause weakness in the body. Simple pokes to certain points on a body can cause extraordinary pain or even temporarily paralysis to a portion or entire body. Learning this was also very essential to becoming a skilled assassin as well as a good fighter. He also learned points to hit on the body that cause death, usually these spots are wear major organs are like the heart however Riki likes to aim for the back. The back holds the spinal cord which supports the body and damage to it can cause death or permanent irreversible damage. In most hand to hand fighting the attacks usually come from the front, Riki on the other hand aims for the back of an opponent. However most opponents won't let that happen so in order to make this happen Riki weakens the opponent by attack places like the knee, ankle, elbow and even foot. Anything to slow an opponent down and capitalize on the opportunity created.
Once Riki joined the Cipher Pol he was placed under the rigorous training to learn Rokushiki which is a super human martial art style. Riki knows all six Rokushiki techniques plus the addition of Rokuogon. With his quick learning ability he was able to master these techniques in a short amount of time and implement them into his fighting style. Furthermore he can combine the Rokushiki techniques with Haki and Fishman Karate and Jujutsu to create techniques that can cause severe damage. For Riki Rokushiki is more of a fighting style he will use where there is a long drawn out battle between him in an opponent because the techniques are geared towards battles that last longer than a few minutes. Each of the techniques Riki has made advancements towards these techniques or has found several different uses for these techniques.
- Geppo: A technique that allows the user to jump off of air itself, Geppo is a versatile technique that Riki uses more than just to jump of the air. The force created by his legs to jump of air is massive and can be used as a weapon. If Riki were to use Geppo in the form of a kick the resulting damage can cause break bones, rupture tendons, and even cause death if placed in the right spot. The power behind a Geppo infused kick is capable of breaking through Tekkai or even a light layer of Busoshoku Haki. When combined with Fishman Karate or his own Busoshoku Haki it can break through nearly anything.
- Tekkai:Tekkei hardens the users muscles to be as strong as iron for withstand and nullify the damage of attacks. Surprisingly Riki has made the most advancements in this technique opposed to his other techniques. With Riki's fishman biology, his muscles harden to be as strong as steel which is a grade above iron making his defense stronger than many other human Cipher Pol agents and users of Tekkai. Riki never hardens his entire body because not being able to move is a disadvantage for him, instead Riki knows how to harden a specific part of his body to block incoming damage. This allows him to not only block attacks but be able to counter after a reliable defense. The reason Riki's Tekkai is more advanced compared to his other Rokushiki techniques is because of his combination with Fishman Karate and Tekkai. There are two ways Riki can combine water with Tekkai and that is from the water on the inside of his body or the water in the environment. The water in the environment can be gathered around the body of Riki and condensed into his muscles which gives them a boost in defense making it harder to break though his Tekkai. This is more useful for protection rather than the other option. The other option is using the water inside his own body to transfer the energy from the attack back onto the opponent or into the ground. This actually softens his Tekkai however the capability to transfer energy somewhere else is very useful.
- Shigan: Shigan is a technique in which the user thrusts their finger at such high speeds into an opponent that it penetrates their body and leaves a bullet hole-like wound. This is Riki's most used technique when performing assassinations because of the swift action. Like his other Rokushiki techniques Riki has devised several advancements in Shigan that increases the potency of its attack. Using Busoshoku Haki or Tekkai, Riki can harden his finger to levels capable of piercing right through dense armor like Tekkai or even Haki. Using his knowledge of the body's anatomy Riki almost always aims for points that greatly weakens, damages, or kills the opponent. Riki can combine his Fishman Karate and Jujutsu to create bullets of water that fly at a high velocity towards targets.
- Rankyaku:One of Riki's strongest techniques in his arsenal, Rankyaku is a technique Riki only has great mastery over. Sending blades of air towards opponents at high speeds has its perks and when the leg behind the blade of air is the leg of a fishman the damage is catastrophic. Riki describes his Rankyaku alone as a force of nature because of the effects of the attack. He is more than capable of splitting any large ship in half using this technique and he can even match the force of a sword slash projection from a master swordsman. When combined with Fishman Karate or Jujutsu the capabilities are increased ten fold. The power of a water infused Rankyaku is said to be capable of shifting the entire current of a small river. This technique came almost natural to Rankyaku because of his increased muscle strength. Haki can also be infused with this technique to increase the damage of this technique. Riki almost always uses this technique exclusively for opponents that push him or situations where destruction is needed.
- Soru:Soru was another Rokushiki skill that came almost natural to Riki. His fishman biology almost doubles the speed of Riki's Soru. Riki can cover far distances in mere seconds due to his speed which helps him close gapes on opponents. This speed allows Riki to get better positioning on opponents or quickly escape a situation that requires a hasty retreat. Riki can move so fast using Soru that he can create after images of himself that hold a temporary physical presence to it. Along with his ability to create his own presence using Kenbunshoku Haki this can cause an enemy to visually believe Riki is somewhere he isn't. This is useful for getting the back of an opponent where he can disable opponents.
- Kami-e: The difference between evading attacks using Kami-e and evading attacks using reflexes is that when using reflexes the user moves only a small portion of their body in order to evade an attack. Portions of the users body lock up and can be sometimes a disadvantage for the user. A locked up muscle or joint for even a second can be capitalized on by skilled combatants because reacting to more than one attack from the same side usually means one of those attack will connect. Kami-e on the makes the body go limp making the user more elusive and agile. Riki uses Kami-e to quickly evade multiple attacks in quick succession or uses the elusive and agile nature of the technique to quickly and successfully counter.
- Rokuogan: The last technique of Rokoshiki, one only obtainable to masters of the fighting style. Riki's use of this technique proves just exactly how much mastery over the fighting style he has. Riki can use this technique through his fist, fingers, kicks, elbows, knees and even headbutts. The unpredictability of the Rokuogan can catch anyone off guard. The shockwaves from Rokuogan from Riki can cause massive damage to an opponent especially if aimed at a vulnerable and unguarded part of the body. This can be used in conjunction with Fishman Karate and Jujutsu to increase the damage of this technique.
Water is all around the environment and if manipulated correctly it can be used as a weapon. Fishman Karate uses the water in the vicinity to impact the water in the targets body, the perfect martial art for an assassin like Riki. Riki mastered Fishman Karate shortly before joining the Cipher Pol. Riki was quickly able to understand the concept behind Fishman Karate and trained with this understanding intensively until he mastered it. Being an assassin Riki's Fishman Karate is centered towards disabling or killing opponents in one attack or the least amount of attacks possile. When the water from his attacks impact his targets body the attacks target the opponents nerves which disables or kills his opponents. The few techniques Riki possesses that cause more damage to the opponent and the area around are infused with a Busoshoku Haki ability Riki posses called Free Flow. The attacks infused with this form of Haki cause as much damage as if the water was coated in haki however the water maintains its liquid state. This free flow technique is mainly used in Riki's Fishman Jujutsu rather than his Karate.
Fishman Karate isn't widely known to be use defensively however Riki being the man he is has found ways to defend himself using Fishman Karate. These defensive techniques focus on parrying opponents attacks and redirecting the flow of water in their body into themselves basically. The concept behind this is to push the water in the body of the opponent the exact moment they make contact with Riki. A simple palm to the wrist to redirect a punch from an opponent can cause enough force to rip the hand right off the opponent. These redirects always cause harm to the opponent because at such close range of the impact, the force alone from Riki's parry can cause damage. The Fishman Karate only amplifies these damage ten fold. Usually along with parrying attacks, Riki will quickly follow up with a simple strike somewhere on the opponent. Being an assassin, these counter strikes are always aimed to kill or disable with Riki aiming for vital points. With Fishman Karate these counters to his parry cause only minimum damage, if infused with Haki or used along with a Rokushiki technique guarantees a kill or serious dismemberment of the opponent.
On bodies of water is when Riki's fishman karate is deadliest especially on the sea. With the limitless amount of water at his disposal it is very difficult to deal with Riki because of this weapon. This is where Riki's ability to cause massive destruction over large area comes into play because of water's form his manipulation options or limitless as well. A simple tap of his foot on the surface of the water can cause massive waves to roar through the sea towards his target. To make his prowess on water even more deadly, the combination of Haki allows him to fight toe to toe against formidable opponents. The addition of Haki increases the damage of attacks and his overall fighting potential.
Water is a shapeless, formless tool of many capabilities. Water can be cut and it can be reformed, it can take any shape it wants and with a manipulator like Riki engineering every intricate design and movement there isn't anything water can't do. Fishman Jujutsu makes use of water in the sea or a body of water and is used as a weapon. Devil fruit user or not, Riki will always have an advantage in the water opposed to on land and fishman jujutsu give him such a gap between him and his opponents. With the power of Fishman Jujutsu miles upon miles and tons upon tons of water is at his disposal. Riki can create currents that can lock or trap an opponent in place and susceptible to more attacks from Riki. Torrents of water that can be shot at his opponents at incomprehensible speeds and unreadable motions that can destroy the body of anything taking the force of torrents shot by Riki underwater. It is impossible for devil fruit users once under water to even lift a finger against Riki which is why when on the hunt for a target that has a known devil fruit he will likely lead them to water. Riki can easily rip the largest of ships apart and tame any beast in the ocean using fishman jujutsu. Not to mention his physical boost when under water, anyone up against Riki will have a difficult time. Like his Fishman Karate and all other skills he continuously trained to get to his level of mastery.
His most advanced ability, Kenbunshoku Haki gives Riki the power of observation and with his advanced skill this form of Haki is a tremendous asset to his skills. One very reason why Riki was recruited into the Cipher Pol was his undeniable prowess in Kenbunshoku Haki. There has been no other person that has been close to matching his observation prowess. There has been many rumors that his observation haki can find a man in the deepest part of the ocean however this of course has yet to be proven and are only rumors.
Awakened as a young child during a near death experience, Riki has spent most of his life advancing his observation haki to where it is now and still works to make advances to it. His ability to sense other peoples presence is keen, so keen that he can sense a number of things about people and his surrounding. His haki can see the definition of surrounding objects as if he were looking right at that object. At the moment, everything is black and white to him meaning that he is starting to be able to see color even hear voices using this haki. Riki determined that more and more usage of Kenbunshoku Haki, he will be able to tell the color of a person's shirt. As for people his haki has advanced to a point that he can see weapons on the person, the power of the person, what they are feeling and even read their minds. With enough concentration, Riki has the ability to observe the minds of people through the presence of the person. Knowing exactly what the person is thinking is Riki's biggest advantage in any mission. Riki will often conceal himself from his enemy before attempting to read their minds. In battle, once he reads the mind of the target it is critical that Riki capitalizes on the information gathered as it is only last for several seconds. The ability to read minds is more useful in gathering info rather than knowing an opponents attack because of less stressful environment in knowing that there isn't an immediate threat rather than locked in a battle in which the opposition may attempt something that prevents him from reading minds. The ability to read minds can stretch to multiple people giving him the ability to basically know an entire conversation between people before words are said. The difference in reading minds and predicting attacks is that predicting attacks is just that, nothing but a guess. While it does allow for users to quickly evade attacks, there are many ways to bypass this. Reading the minds of opponents during battles allows for him to know for sure that what the opponent is going to do is what is going to be done. Reading minds during battles however is rather difficult for Riki as sometimes he is under too much stress to successfully read his enemy mind and so he just relies on predicting.
The ability to predict opponents attacks is advanced like no other. With the ability to sense the presence of a person, Riki can tell what the opponents is going to do especially within close range of Riki. He also is noted to have the keen ability to analyze the slightest movement in a person's body through their presence and make adjustments before the attack lands. This works very effectively for short range combat situations. The weakness of Kenbunshoku Haki is that inherently random attacks cannot be predicted. Riki however has bypassed this weakness. By concentrating his Kenbunshoku Haki 5 feet from himself in all directions he can sense anything. By doing this Riki's Kenbunshoku Haki acts more like the ability to see in every direction instead of sensing. It is directly connected to his sense of feeling which allows him to bypass the weakness of this Haki and react accordingly.
With his advanced Kenbunshoku Haki, Riki has a few unseen and uncommon abilities that separates him from common Kenbunshoku Haki users. The first is the ability to conceal his own presence from the few of other Kenbunshoku Haki users. The reason the Minks were able to sneak up on a proficient user of Kenbunshoku Haki user like the Pirate King Monkey D. Luffy was because they could masterfully conceal their presence from him. With his mastery over Kenbunshoku Haki Riki stumbled upon this ability to do the same. His ability to conceal his presence using Kenbunshoku Haki is so acute that during hand to hand combat against an average user of Kenbunshoku Haki he can conceal his presence enough to prevent the enemy from predicting his movements. Next is the ability to create a presence like his own and insert it in places to trick his opponents. This greatly affects other users of Kenbunshoku Haki because when he does this and they have no physical view of him, the presence Riki inserts into places can and will be sensed instead of himself. Riki's manipulation over his presence is like no other, to people even other Kenbunshoku Haki users he is virtually invisible.
Riki unlocked Busoshoku Haki during his time as a member of security teams for the noble he was protecting. It was unlocked during training with members of the security team, Riki landed a strike that had more power than usual and nearly killed him. He did the same thing again during another training session and after research he was able to find out exactly what it was which was haki. He knew about this form of Haki however at the time he had no desire or need for it because he hadn't encountered a situation where he needed the reason to have Busoshoku Haki. After unlocking it, he trained with it being able to coat a certain part of his body in this form of haki to increase the potency of his attacks mainly his Rokushiki and Fishman Karate techniques. An even larger concentration of Haki coats Riki's body parts in a black layer of Busoshoku Haki that causes even more damage. It took Riki less than a year to obtain this level of Haki which allowed him to match up to an average person in the New World however he wanted find a way to use Haki in any shape, size, and form similar to water. The problem was he could only figure out how to coat his limbs and objects he held with Haki and could extend this outward. He heard of the tales of many users of Busoshoku Haki who could perform extraordinary feats with this form of Haki and he would come up short.
- Free Flow: Free flow is a technique devised by Riki when seeking ways to improve the potency of his Fishman Karate and Jujutsu. There are individuals that even while underwater against a fishman still are so overwhelmingly powerful that the boost fishmen get underwater doesn't give an advantage. The same went for Fishman karate, some beings in the world could withstand attacks against a skilled user of Fishman Karate like Riki. Haki was the answer to this however the problem was Haki was limited to hand to hand combat, the only way Riki could increase the potency of his Fishman Karate techniques at the time was hand to hand combat. Direct contact with a person was the only way his Fishman Karate techniques could cause more damage however fishman jujutsu was out of the question in trying to increase its potency. Sentomaru was capable of using Busoshoku Haki without making contact with his opponent. Riki figured out a way to do this however implementing it with his Fishman Jujutsu and Karate didn't work the way he wanted to. It would be a forceful attack that would cause collateral damage that he didn't need. He wanted to Haki to act as water so that when it hit opponents it would seem like just water but do much more damage. To do this, Riki my first coat his body in a layer of haki, then let it seep out of his body like sweat and into the water he is using. At first this was difficult and took a long amount of time to do because combining Haki with water would cause the water to harden. However over time he was able to get a hold of controlling how much haki to place in water. Free flow only works with water because without something to attach to the Haki simply disperses. The end result are attacks that look like regular water but are boosted by Haki. Devil fruit users are greatly affected by attacks from free flow and is very deadly to them.
With the Hie Hie no Mi Riki has access to more abilities than just simply freezing over an object. Riki can control how thick or thin the ice he create can be. The more thicker ice can be used to encase a target with tons of heart stopping ice that is extremely difficult to escape out of. Thick ice can also be used as a defense to block attacks to protect himself or whoever else needs the protection of his ice. Thin ice is used for more attacking purposes because of sharp edges and spiked edges. Additionally when manipulating thin ice, the speed at which the ice moves is extremely fast and versatile. If not on guard an opponent can be skewed by thousands of ice shards that can easily penetrate skin and bone to get into vital organs and vessels.
Aside from physically attacking the user, ice has effects on that body that are difficult to reverse. When an opponent is somehow frozen by Riki's ice, they are susceptible to shattering if hit with a simple force. Additionally if not thawed out properly, an opponent can unintentionally kill themselves. External heat can cause the frozen tissue to crack or cause the cold blood on the surface of the skin to circulate into the heard and cause a heart attack. Often times Riki will let an opponent hit him so he can instantly freeze them upon contact which is almost always fatal to the opponent. He can also project the coldness of his ice outward from himself and from his attack as a vapor that can quickly coat anything it touches in a layer of ice. Once the smallest bit of ice is latched onto the opponent Riki can cause that ice to grow and effectively harm the opponent. The closer the target is to Riki or his ice attacks the more prone they are to the freezing affects. If an opponent does not have a way to combat the ice that freezes over them death can come quickly which is why Riki is also called the Angle of Death.
Riki has unlocked ways to bypass weaknesses of himself and his devil fruit. Seawater can be easily turned in to ice upon contact with water. Fire is something that can be used to melt ice and is an element many people have use of even without the augmentation of a devil fruit. Riki however has become so advanced in his use of ice manipulation that he can easily freeze over ice by causing molecules in the fire to slow down enough so that his ice can freeze it. Haki can be used to touch the intangible body of Riki when he transforms into ice however to bypass this he can transform parts of his body to escape and attack using Haki. Attacks that are meant to be a surprise can still be evaded because of Riki's ability to transform into his element upon reflex like many other skilled Logia users.
With any Logia devil fruit there is the ability to generate an endless amount of their specific element. The difference with Logia type devil fruits is that some have the undeniable strength to wipe out entire landmasses or have the power to cause massive damage over an entire battlefield. Then there are the logai devil fruits that don't have the destructive power of other but instead can be used to restrain opponents. The Hie Hie no Mi has the potential to be used in both ways. Riki can easily contain opponents by making an entire battlefield his but having the power to wipe out entire armies or destroy landmasses is something the Hie Hie no Mi does differently.
Since ice is a solid state element, unlike many other devil fruits he can not only turn himself into ice to keep from getting hit by physical attacks but he can imbue his ice with Haki. When Riki concentrates enough Haki into ice it turns black and with this ice he can cause a number of effects. One of the most staggering effects of black ice is that it cannot melt. Not even extreme heat emitted off an element like Magma can melt the ice because when combined with Haki its not only ice. The life force of Riki's Haki keeps the ice in its solid state and once imbued with Haki the Haki does not fade from the ice unless commanded to by Riki. The problem with this form of ice is that to make large constructions or use large scale techniques composed of black ice uses a large amount of Haki. Usually Riki cannot continuously use this form of ice for long drawn out periods of time or he'll deplete his Haki reserves. The use of black ice is something Riki has to use intelligently and cannot spam like his regular ice. However, he can coat his ice in the invisible layer of Haki which he can pour out in larger amounts than the concentrated black coating of Haki.
The Hie Hie no Mi give Riki the ability to freeze almost anything over in ice in an instant. With the Hie Hie no Mi Riki has the ability to literally stop anything by simply freezing it. It took Riki a few years to achieve such a grasp over his power, however the ability to freeze literally anything in ice became like second nature to Riki. Moments in when he deeply freezes something over are moments that Riki describes the world feeling as if time has stopped. This is because with the Hie Hie no Mi when he deeply freezes over an area everything at the molecular level is frozen solid. This even includes air itself or anything that moves at a high rate of speed.
Riki was born on Fishman island to an unknown mother and father which is why neither himself or other fishman know what species of fish he is. In fact Riki never knew his mother nor father and instead grew up with a proctor of Fishman Karate. Riki was left on the doorstep of the Fishman Karate dojo. The proctor found Riki when leaving the dojo and took him home and took care of him. He nurtured Riki, took care of him and even taught Riki himself. Around the age of 4 when Riki could start doing things on his own, the proctor started teaching Riki both Fishman Karate and Jujutsu. Within 4 years Riki was a senior student at the Dojo, having learned advanced techniques and skills. Riki started teaching fishman that came to the Dojo to learn Fishman Karate and Jujutsu. It was thought at that time that Riki would become a proctor at the Dojo once he got to a mature enough age however things changed.
At the age of twelve, Riki decided to go to the surface of the world and explore it. He had never been anywhere near the surface and he simply wanted to explore the world above the sea. He was warned by his master and many other people of the hardships on the surface including some of the humans hate for fishmen however Riki disregarded these warnings. The day Riki ventured to the surface, he encountered pirates and was captured. They decided that selling Riki to slavery would bring them a bunch of income and so they did, the sold him right to a Noble. Riki's first days on the surface weren't off to a good start, and things would only get worst.
Riki was surprisingly a good slave in the eyes of his owners. He did everything they wanted him to do and sometimes more and according to the noble he was too good to be a slave. The skills he had the noble knew he could use to easily escape but he didn't which is why instead of keeping Riki, he traded Riki to another noble of higher status in the world. Again Riki shined to his new owner, doing things right and things other slaves couldn't or wouldn't do. Riki was rewarded with becoming apart of his noble's security team. When Riki was around no harm would come near the noble. During these years as a member of security, Riki unlocked two out of the three forms of Haki and mastered his own Fishman Karate and Jujutsu techniques.
Around the age of sixteen, Riki was approached by a member of the Cipher Pol. Under the recommendation of multiple powerful nobles and testaments of his skill the Cipher Pol had an interest in Riki. The first time they approached Riki, he thought it was an attack on his noble's life and so he engaged the agent only to be quickly subdued by the agent's overwhelming power. Not much was said between the two, the agent was simply there to give Riki something to think about. Joining the Cipher Pol would give Riki access to so many things and he would have power to do just about anything he wanted. The agent gave Riki info, a location of where he should go if he would decide to join the Cipher Pol.
However Riki, was assigned to the security team of another noble one that would what he thought be too time consuming to even thing about joining the Cipher Pol. One day while sailing across the sea to get to an island his noble wanted to venture to, they were attacked. The attackers weren't pirates as usual or raiders, these attackers were more organized. It was like nothing Riki or anyone on that ship had seen before, the synchronization of attacks was as if the attackers gathered intelligence before attacking. They knew what Riki and the security team were going to do before they did it which brought everyone on that ship to their demise. The attackers killed everyone even the noble but kept Riki alive. They brought Riki onto their ship and revealed their identities as none other than the Cipher Pol. The Cipher Pol planned to kill off the noble because the noble was making deals with the Revolutionary which compromised the safety of a member of the world noble. They set it up for Riki to be switched to guarding the noble so he could get an idea of the Cipher Pol's prowess in information gathering and execution of attacks. Riki was indeed impressed however it was still his decision to join or not they weren't just going to bring him into their ranks, Riki would have to be willing to do so on his own.
Once he joined the Cipher Pol he endured rigorous training under proctors he wasn't so used to back at Fishman Island. He however was a quick learner and became adapt in Rokushiki. Riki wasn't training to be in one of the known Cipher Pol units being CP-1-8, he was training to be in one of the two elusive units CP-9 and CP-0. With Riki's quick learning and unbelievable skills it would have taken him 8 years to get into CP-9 however he wouldn't settle for that. Before encountering the Cipher Pol Riki was devoted to guarding his Noble's life, he had taken hundreds of hits and killed thousands of people for them. Anyone that knew his history considered it crazy that a former slave who was enslaved by the exact people he would protect. It was all Riki knew and he enjoyed doing it and he wanted to continue doing what he did. CP-9 focused primarily on missions to assassinate targets while CP-0 is under the direct command of the World Nobles. Riki decided that he wanted to go through being a CP-9 agent then become a CP-0 agent.