Martial Arts Prodigy: In the beginning Shi-Woon appeared as a non-talented individual in terms of learning Martial Arts. However, after healing his Three-Yin Body Type and started training he was revealed to be far more gifted than he seems. He displayed observation skills of an extremely high level. This has been shown various times throughout the series. He was able to learn how to use Soul-Crushing Strike in half a day and the Walking Techniques after one night. Chun-Woo Han was astounded with both cases as normal people take several months to "only" understand how the same techniques work. Equally astounded Kang-Sung commented that Shi-Woon may be a "dragon", just like his master. Additionally, he was able to learn and enter the Outer Body Training Method after one day of training, something that takes a year for talented individuals and an average of five years for normal ones. Lastly, he was able to learn all the Black Heaven & Earth School and Nine Art's techniques he knows from videos left to him by his former master and without proper instruction from anyone. Many Murim-ins, especially highly experienced masters, that observed his fighting outright believed and claimed that the information of him practicing martial arts for just a few months at best to be false due to his abnormal and supernatural progression in martial arts. Also a great deal of them, in particular So-Chun Hyuk, declared that they wish to see his future as a martial artist. A testament to Shi-Woon's incredible talent in martial arts is that he is the first and only person that So-Chun Hyuk ever thought of becoming his rival a position that his own senior, So Jung Chan, has not even earned himself. Recently when Shi-Woon instinctively invoked the Cry of the Phoenix technique over Elder Kwon's death like Chun-Woo Han did over Shi-Ho's apparent death, he had invoked a different form of the Black Origin Threshold. This led Kaiser, the leader of the Black Forest Defence, to state that Shi-Woon would become a greater "Demon King" than his master.
Real Master Martial Artist(Black Heaven and Earth Style, Nine Arts, Sun-Woo Style, and Artists' Society Style): His actual rank has never been clearly stated but it can be identified through his fights so far. In terms of Spirit, he is shown to have one on the same level as his master thanks to his resolve (death or victory) since he entered the Murim. His Ki was equally high level due to the ingestion of the Il-Wol Sin-Dan and assimilation of it using the Black Heaven and Earth Technique. This, additionally, increased the size of his meridians, which is the last step of training in order for a Murim-in to reach the Real Master Level. This along with his abnormal observational skills allowed him to grow in a speed that even experienced and great Murim-in cannot comprehend.
Rank Succession: Normally a murim-in grows with time and training and passes through set ranks as one develops. However, in Shi-Woon's case there is no clear point that determines his passing from one rank to the other because of his unnatural training and development. Hence, his rank succesion will be estimated based on the series' events and comments from Murim-ins.
Practitioner: Due to his Yin Body Type his body was weak and unable to learn Martial Arts. By ingesting and assimilating the Il-Wol Sin-Dan not only was his condition cured but his Ki reached the level of Real Master while his physical body was still weak. Within a few days he managed to stabilize its circulation and after several days his body was starting to catch up through basic physical training. After learning the Soul Crushing Strike and fought against So-Chun Hyuk, who called him skilled, it is assumed that he is already a practitioner.
Expert: Within a couple of weeks Shi-Woon was able to catch off guard and defeat Kang Oongsan, who is stated by So-Chun Hyuk to be an expert in a specific style with one attack. Hours later, while running from the Martial Arts Alliance he was reported as an expert due to his skill of using Soul-Crushing Strike and Walking Techniques.
Master: After learning and training with the Outer Body Training Method, Shi-Woon was able to hold his own and, by catching of guard, defeat Yong-Hyun Yan, who, according to Jae-Kyu Kwon, is a master rank Murim-in. Later, after training using the Jin-Gi Dan his skills improved again. Although injured and tired, he was able to fight equally with Yong-Hyun Yan and defeat him a second time. This is the point of his transition to a Master.
Advanced Master: During the invasion of the Nine Dragons High School by the S.U.C. he has learned how to efficiently use the minimum possible Ki and produce the best possible outcome with it, which surprised even Ha-ru. By entering into Black Origin Threshold he was able to land strikes against Ryuji, who was able to fight against Jae-gal (a real master). After he healed and his body underwent Overhaul Rebirth his skills (fighting against Jung Lae Won and Ju Sang-Sik after defeating numerous agents and losing lots of blood) reached the level of Advanced Master.
Real Master: After training with the Triple Blossom Meditation Technique, where he continuously sparred with So-Chun Hyuk, a renowned genius even among the Ten Grand Masters, his skills improved greatly. He was able to easily defeat the Murim Police Chief with just two attacks while the latter's disciple, Jung Lae Won, was unable to land a hit on the former and was easily defeated. Later he fought against Ha-ru, Yong-Hyun Yan and Ji-Woo Li (three of the S.U.C. captains) simultaneously and was able to hold his own despite being exhausted from fighting the grunts of the S.U.C. earlier. His skills also surprised Chun-Woo Han and Advanced Masters, such as So Jung Chan and Julia, were unable to comprehend his techniques. Also during his fight with So Jung Chan, Shi-Woon displayed greater observation skills as he was able to easily counter all of the former's attacks and even copied a counter technique that So Jung Chan demanded to know where he had learned it. Upon activating the Black Origin Threshold from Elder Kwon's death in a new form, Shi-Woon is able to fight evenly against his master, Chun-Woo Han, displaying the same level of power Goomoonryong has and managed to push him back a few times (though Ju Sang-Sik and Kang-Sung noted that Goomoonryong wasn't going all out) but he was eventually subdued. Despite this, many of the witnesses (including Ju Sang-Sik and Te Ul) admitted that had Shi-Woon learned martial arts properly after undergoing the Overhaul Rebirth then he would have defeated his former master in that fight. This is assumed to be the point of his transition to Real Master.
Goomoonryong-Level Spirit: Even in fights where the odds are against him, Shi-Woon has displayed an indomitable will and not backed down from a fight since receiving his first, albeit offhanded, lesson from Goomoonryong. Whether it is bravado, stupidity, or a mixture of both, Shi-Woon's willpower has impressed many martial artists, including So-Chun Hyuk. Instead of his unique techniques or Ki reserves it is his inhuman determination and spirit that most often convinces other Murim-in that he truly is the disciple of Goomoonyrong. Recently So-Chun Hyuk stated that Shi-Woon is the superhuman that surpassed the instincts of mankind which allows him to terrify others with his spirit alone rather feeling fear himself. Ju Sang-Sik also commented that Shi-Woon is crazier than his own master, Goomoonryong, which also hints at this form of spirit.
Superhuman Healing Factor: By ingesting and assimilating the Il-Wol Sin-Dan, Shi-Woon received Ki equivalent to several of the top martial arts masters . His body became a living spirit medicine and developed a healing factor that, according to Chun-Woo Han, rivaled the Planaria  and this allows him to heal any non-fatal injuries within half a day and any level of fatigue will disappear overnight. Seung-Jae Bae had declared Shi-Woon to be a "walking" spirit medicine due to the excessive amount of Ki his body possesses that gives him an incredible healing rate that Yae-Won noted to be abnormal even by Murim standards. Seung-Jae also said that there are several places in his body generate Ki independently of each other which gives him the advantages of negating accurate point attack. Wounds from knives healed within the day and the injuries from his fight with So-Chun Hyuk within a night. Fatal injuries would still need medical assistance but from the moment his body is no longer at risk his healing capabilities will take over. Such injuries include the forceful removal of the Thousand Needle Restriction that Ju Sang-Sik used against him and the injuries from the Chaotic Heavens Destruction Strike. The later was an astounding case, since even with the medical assistance he recieved he was thought to be a lost case but showed a remarkable turn, healed in a few days and regained conscious. It is possible that, since during that time he underwent Overhaul Rebirth, his healing factor was enhanced as well.
Immense Endurance: Shi-Woon's stamina and pain endurance has surprised many top murim-ins including So-Chun Hyuk, Kang-Sung and Ju Sang-Sik. He is able to fight for long periods of time and stand up after recieving various blows from his opponents. Many comment on the impossibility of his endurance as in many cases he is supposed to have fainted or even died several hits before. When Shi-Woon had activated the Black Origin Threshold he was able to continue fighting even after being dealt with fatal wounds that terrified even the S.U.C. Recently after undergoing the Overhaul Rebirth and entering the Triple Blossom Medition, Shi-Woon is able to endure punishing strikes from even his own former master, Chun-Woo Han, and remained conscious despite the damage.
Enhanced Strength:Shi-Woon has blown apart doors of reinforced glass with a single punch after fighting for hours and ripped a car door off it's hinges without any effort. He managed to knock back and throw Ryuji a former student of Un-Wol through a window with ease. After undergoing the Overhaul Rebirth, Shi-Woon is able to send skilled Murim-ins like the Murim Special Ops agents flying back with simple punches and left many of them severely injured with one of them questioning if he was a monster. After using the Cry of the Phoenix and having activate a new form of the Black Origin Threshold, Shi-Woon displayed enough strength to push back his former master, Chun-Woo Han, with one punch which the latter was barely able to block (albeit the latter was caught off guard then). During their fight, Shi-Woon's attacks were able to demolish the surrounding structures similar to his master.
Immense Agility: Due to the natural strengthening of his body from Ki circulation Shi-Woon has supernatural agility. He is agile enough to fall from a height of 4-5 stories. Recently he has shown the ability to effortlessly flip and jump around a fight using most surfaces to his advantage.
Enhanced Senses: Since the Overhaul Rebirth, Shi-Woon has shown that, his body feels lighter and he is more sensitive to things around him. His five senses are enhanced making it possible for him to feel and hear things that should not be possible under normal circumstances. He is even able to tell how strong a person is and their intent towards him from their ki alone even if they are suppressing it. His reflexes have also increased dramatically to the point that his body acts without him realizing it.
Ki-Center State: After ingesting and assimilating the Il-Wol Sin-Dan his Ki-Center grew significantly. During his treatment to heal it and after the basic Ki-Center was formed, it was noted by Hyun Won-Jae that his Ki-Center tries by itself to grow bigger, something he had never seen before. During that time he was able to perform martial arts to a certain degree . After undergoing Overhaul Rebirth it was completely healed by itself and it is assumed (based on the comments for his Ki by Ju Sang-Sik) that it has reached the size that it was attempting before.
Overhaul Rebirth(Hwan Gol Tal Tae): It is the phenomenon where excessive Ki within the body rearranges the organs, bone structure, and overall physique of the body. This phenomenon was witnessed on Shi-Woon while he was healing after the events of the Soldiers Under Command's invasion of the Nine Dragons High School. It is assumed that this phenomenon was responsible for the complete healing of his Ki-Center. Ju Sang-Sik stated to Shi-Woon that undergoing this phenomenon gave him the potential to become the strongest master in all of murim even surpassing his former master, the Goomoonryong himself. When describing the effects of the Overhaul Rebirth to Shi-Woon, Ju Sang-Sik stated that Shi-Woon's body became more free and is no longer within the boundaries of human limits and said that in order for him to become stronger he needs to forget his former limitations. In other words he is now in possession of a "superhuman body" (as said by the ghost doctor) and can learn abilities normal people couldn't even imagine.
Stealth: Shi-Woon gained the ability to hide his Ki much more effectively than people who are above master level. This ability allows him to move around unnoticed and to hide from even experienced martial-artists as is demonstrated in the events following the S.U.C.'s attack on his school. Only grandmasters have been able to detect his presence.
Inexperience: Due to his lack of experience in fighting he is vulnerable against an opponent with more experience as shown with his duel with So Jung Chan over the fate of Seoul whom he noted to be below his younger brother in term of skills, but he had more experience. He is unable to use his skills and techinques to the best of his abilities. Only his master could teach him however they have turned into enemies.
Black Heaven and Earth Technique(Hyunchunjigong): A legendary Ki circulation technique taught to Shi-Woon by his master. Goomoonryong remarked that he only taught this to Shi-Woon because it was the only Ki circulation technique he knew of strong enough to disperse all of the Ki given off by the One Moon Divine Dan.
Black Origin Threshold: A secret technique learned from his master Goomoonryong. It is a technique derived from the Black Heaven and Earth Technique. However unlike the Black Heaven and Earth this technique fuels it's power from emotions especially rage, because of this the user gains a strange form of Ki which causes the user to gain a huge power boost, a dark powerful intimidating aura, along with some sort of steam or smoke to come out of his or her mouth. Though this technique is very powerful it has a side effect, which makes the user's entire ki become reversed causing the user to lose himself in a frenzy of blood lust, because of this, the Black Origin Threshold is a forbidden technique. Despite it being forbidden the Black Origin Threshold has become a technique feared by the Murim. The only two living users of this technique are Shi-Woon and Goomonryong.
Soul-Crushing Strike: An Inner Power technique in which the practitioner circulates Ki through his body and releases it through his fist at the same time he extends his hand. This technique requires a large reserve of Ki for extended use and the ability to synchronize the release of Ki with the movement of the body.
Lightning Strike: While his Ki-Center was broken Shi-Woon used the Soul-Crushing Strike without Ki circulation.
Walking Techniques: Techniques using the ankles to perform specialized steps. Shi-Woon witnessed each of these once and managed to replicate them the next day in battle.
Focus Stomp (Jinwongak): A kicking technique that is powerful enough to easily break through the bones of his opponents. The practitioner uses one leg to stomp the ground. The technique is capable of literally crushing concrete and cutting through flesh and bone. Due to translation error, many think this is a new technique, however, it is clearly written in the raw version as 진원각 (Romanized as Jinwongak).
Phantom Kick: An aerial kick that involves twisting the body while in mid-air to land a powerful kick. This technique can be used as intended or when the opponent has a hold of the user's leg and is either throwing or holding them in place.
Cry of the Phoenix: A sound based technique that allows Shi-Woon to let out a sonic scream that is so powerful it can deafen those nearby and its force is so great that it can cause severe turbulence for a helicopter and shatter apart the surrounding structure.
Iron Wall Stance: A fighting stance of the Sun-Woo Clan, his left fist is held out front as a shield to ward off opponents. If an enemy shows an opening or takes a step closer, then the other fist is used like a hidden spear.
Outer Body Training Method(Hyun Hwan Shim Yun Gong): Learned from Elder Yae-Won of the Artists' Society School, it teaches martial arts in a deep state of meditation. The technique creates a mental image of a new body with Ki-circulating normally and fights with previous opponents in the deep mental meditation.
Abyssal Insight: A technique of the Outer Body Training Method. It allows Shi-Woon to memorize any technique that he has seen even once, regardless of the martial arts style, and make it his own. Due to Shi-Woon's high observation skills, he can master new techniques much faster.
Triple Blossom Meditation: A form of the Outer Body Training Method. During its use the user is in a state of mind that causes three flower blossoms to appear on top of his head. This seems to be an enhanced form of the Outer Body Training Method as when Shi-Woon entered this stage he released an immense amount of Ki that greatly surprised Ha-Ill Gang, Jin-le Kwon, and Sera Kang along with replaying his spar with So-Chun Hyuk unlike the the original form that only recreates the previous opponents he fought with their strength at that time.