Hardner is a pale, well-built man distinguished by his great height, a known trait of him, which comes with very long limbs. He has an elongated, squared face with marked features and a mildly prominent nose, light azure eyes topped by thin eyebrows, and a distinctive black tattoo covering his large forehead, this taking on an almost flat "V" shape with two small spirals near each edge; something which makes it somewhat reminiscent of a pair of wings. As the Captain of the Blue Guardians, his azure hair is kept in a short cut, with a single tuft located on top of his head, going from its back to the forehead, jutting upwards; in the past, Hardner's hair was shown to be noticeably longer, with wavy strands of hair topping his head and protruding in every direction. Ever since his first days in the Blue Guardians, both of his relatively large earlobes have been adorned by simple, round metal earrings. During his first appearances, he retained the injury gained from the ship crash which caused the death of almost every Blue Guardian from the first generation, and which cost Hardner his left forearm: in its place, a large gun was present, secured to his stump. After such weapon's destruction, Hardner employed the powers of his Mother Dark Bring Anastasis to regrow his lost limb, thus having his arm restored to its original state. While he first appeared aboard the Albatross, Hardner also donned a simple pair of frameless glasses with square, purplish blue lenses; these, however, where destroyed when Belnika tried to assault him.
When he was first introduced, Hardner donned a regal attire testifying his role as the leader of an organization whose power rivalled Demon Card's: he sported a light shirt with intricate, spiraling dark motifs and edges adorned by a succession of light and dark parts, paired with dark pants and footwear, with what looked like fur jutting outwards from the ankle area. Over his shirt was a light plate cuirass, which in its upper part had four belts secured by buttons, two on each side, meant to be connected to the massive, rounded blue pauldrons covering his shoulders, possessing light edges and being adorned by a white Blue Guardians' emblem. A wide, similarly colored armored collar was present around Hardner's neck, sporting a series of white hollow rhombs containing small black circles as decorations, with the addition of golden upper and lower edges, and hanging from his wide shoulders, covering the upper part of his pauldrons, was a long, light grey cape, which on its outer size bore a motifs similar to the one on his collar, with black rhombs and circles, and which was secured below the Captain's neck by a clasp which bore Anastasis. An intricately decorated ring circled his right middle finger.
After disembarking from the Albatross alongside Belnika, Hardner is shown wearing a much simpler outfit: his armor is replaced by a long, light coat reaching down below his knees, possessing a high and wide collar and cuffs covered in light fur, which alternates plain sections to parts adorned by various numbers of lines, making it look like the cloth is composed of bands joined together; below it, his garish shirt is replaced by a simple, plain dark one, sporting a partially open high collar, with a light sash circling Hardner's waist. The Captain retains his pants, footwear and cape, but the latter has visible epaulets added to it in correspondence to Hardner's shoulders.
During his days in the Blue Guardians, he wore the group's signature high-collared jacket, light in color but possessing dark edges and dark stripes on the outer sleeves, ending in motifs reminiscent of spades, over a dark shirt bearing a light Blue Guardian symbol, and, again, dark pants and footwear. More instances had him wear jackets with similar designs, but lacking the motifs and bearing pockets, and in one of them he was also shown wearing a jacket with a similar design paired with a cape.
During his days in the original Blue Guardians, Hardner used to be a friendly and cheerful individual, a happy-go-lucky air pirate racing across the sky, searching for treasures every day with his comrades and wife, Sophia. However, the sudden crashland of the Liberal Familia that tragically killed all his friends (minus Yuma) heavily brought him into deep despair after seeing his wife dead and to his presumption, his unborn child. This resulted in his solo journey as desperateness to run away and forget everything of that tragic day. As the Captain of the refounded Blue Guardians, Hardner changed to be ruthless and cruel tyrant, brutalizing and insulting subordinates of him as close as Lunar, and being willing to make people suffer to achieve his goals, such as when he forced Belnika to do as he wished by torturing Jerry Bourne, even going on to make sadistic remarks and rejoice at Belnika's despair. He was also willing to shoot his best friend from the old days, Yuma Ansect, in the head, subsequently going on to gloat about the seeming killing. He seems to enjoy toying with his foes, appearing in front of the Rave Warriors when they boarded the Albatross and teasingly pretending to show off his etiquette of Captain by introducing himself, subsequently informing the intruders of Makai's incoming destruction. He has also developed a certain fascination with the concept of decapitation, wielding a sword with a blunt tip, which he refers to as the Executioner's Sword, whose solely purpose, according to him, is to behead opponents, and often remarking about enemies' incoming "executions" at his hands before assaulting them. In addition, he believes that Mother Dark Bring Anastasis has chosen him to be its owner, and his possession of it makes Hardner think of himself as immortal, referring to himself as the "warrior that possesses an undying body". He gets extremely upset and enraged every time someone tries to hinder his path towards Endless, losing his cool and frantically assaulting the responsible. Hardner also appears to enjoy fighting, as shown when he welcomed his battles with Haru Glory and Let Dahaka as pastimes of sort, and to be fond of cigars, being shown smoking them during several instances; following the seeming end of his battle with Let, Hardner went on to light a cigar, telling him it was "a little too glorious to signify the end of your fighting days", and teasingly stating that, in spite of this, Let didn't have to thank him for what Hardner saw as an "honor" of sort.
Hardner gave several explanations for his wish to summon forth Endless in Makai, something which would have caused the latter world's end. At first, he made claim that he wanted the creature to reduce the world to nothingness in order to satisfy his extreme greed, which was so great that Hardner desired things such as the sky and the ocean for himself (such first reason was also hinted during his younger years in the Blue Guardians); he even went on to declare destruction the "ultimate creation", stating that "as everything is lost, everything is gained". Hardner revealed that such a goal was to be achieved through the use of the Altar of Birth, which would have first fused him with a user of Etherion (which Hardner saw first in Belnika, and later, after the latter was revealed to lack the power, in Elie), and then would have made him and Endless as one, turning the Captain into a god. Hardner's real goal, however, was just to forget the terrible accident which had taken his wife and unborn child's lives (though the latter was revealed to have survived), an event which he could never get rid of and which kept tormenting him, with him unable to vent his wrath or put an end to his pain. The Captain believed that Endless, as the "king of oblivion", could have realized that single wish of him.
Following his defeat at Haru Glory's hands and the revelation of his daughter Nagisa still alive,  Hardner seems to have returned to his former personality, tearfully thanking Yuma, acknowledged again as his best friend and asks to keep raising her in his stead.
Dark Bring & Abilities
The Captain of the Blue Guardians, Hardner is a powerful and experienced air pirate commanding an immense fleet of flying battleships, ruling them from his flagship, the gargantuan flying fortress Albatross. The number of soldiers under his command, according to his own words, ranks into millions, and his group was acknowledged as the most dangerous one out of the three formed after Demon Card's temporary downfall (namely Doryu Ghost Attack Squad, Onigami and Blue Guardians itself), having defeated 136 other teams. His use of a Mother Dark Bring, alongside his own skills and his years of fighting experience, make him a fearsome opponent, who was shown capable of fighting pair-to-pair with Haru Glory, the Second Rave Master, even managing to momentarily overwhelm him, as well as of defeating Let Dahaka, one of the strongest exponents of the Dragon Race.
Highly Perceptive Combatant: One of Hardner's most valuable assets is his long experience on the battlefield, which has granted him sharp senses and an analytical mind able to examine enemy tactics and react accordingly (though this seems to partially give out when he becomes enraged). He referred to the smokescreen which Haru Glory generated with his Explosion sword as a "childish antique" before nullifying it with his Anastasis. His knowledge, as evident of his role, also includes airships, as shown when he could deduce that one of the Blue Guardians' ships nearing the Albatross didn't belong to his group simply by hearing its engine's sound.
Enhanced Strength: A seasoned fighter, Hardner has displayed a considerable amount of physical strength: when swinging around his Executioner's Blade with a single hand, the force of his slashes is high enough for him to cut down objects which are away from the physical reach of the blade through sheer air pressure, managing to slice off more than one thing several meters away from him. When wielding his sword with both hands, Hardner is shown able to generate very large and damaging bursts of air, as well as to cut through rock, generating small shockwaves. His defense is just as strong, with him parrying a downward slash from Haru Glory's Explosion sword without stepping backwards. Hardner's strength is not limited to his use of the sword, as shown when he could punch Let Dahaka, a strong and resistant member of the Dragon Race, knocking him to the ground.
Enhanced Speed: Hardner's speed and reflexes have been honed to a great extent by his experiences on the battlefield, and they allow him to rapidly react to attacks, as well as to perform his own attacks fast enough to overwhelm his opponents. He was shown easily avoiding a surprise assault from Yuma Ansect, who suddenly came crushing through one of the Albatross' windows, and could momentarily outdo Haru Glory in terms of speed, performing an impressive barrage of slashes which Haru couldn't keep up with.
Master Melee Combatant: A veteran air pirate, Hardner possesses great mastery in melee fighting. He has shown to possess specialist skills in swordsmanship, fighting on equal terms with an accomplished swordsman such as Haru Glory for a lengthy amount of time. His blows are noted to be both extremely strong and fast, and he's shown capable of flawlessly parrying and deflecting rapid barrages of enemy assaults. Hardner usually wields his blade with a single hand, placing his other hand on the hilt only when he wants to perform particularly strong attacks, and relies solely on slashes, due to his signature Executioner's Blade lacking a sharp tip which could be used for lunges. While favoring the use of his advanced swordplay, Hardner has proven himself to be a proficient hand-to-hand combatant, capable of packing strong punches and kicks: he was shown attacking and hurting an expert martial artist such as Let Dahaka even without the aid of his sword, and is able to effectively combine swordsmanship and unarmed blows during battle.
Anastasis: While travelling alone after his wife and comrades' death, Hardner came across a unique object, which he would eventually come to consider a sentient being of sort, making claim that it had "chosen" him: this object is Mother Dark Bring Anastasis, one of the five pieces of Sinclair, the original Dark Bring. This harnesses a power which the Captain referred to as "regeneration": Anastasis allows him to revert both living and non-living things from their current state to a previous one, no matter the lapse of time which separates the two of them; a capability which can be used from a variety of purposes, being particularly effective when employed in battle. He has proven himself capable of altering the state of buildings, plants, air and even humans, as well as his own body. When employed on himself, Anastasis provides Hardner with one of its most valuable assets: it grants him the ability to almost instantaneously heal whatever injury he may receive, no matter its graveness. Hardner was shown healing himself from small bruises and grievous holes in his body with the very same ease; not even instant-kill attacks are effective against him, as shown when Let Dahaka pierced through his heart with a punch, and the Captain stood back on his feet unscathed in mere moments. He made claim that, even if his head was to be severed, the few seconds of life left to him would be enough for him to regenerate. Anastasis can also heal injuries which the user received prior to obtaining it, as shown when Hardner used it to regrow his missing left arm, which he had lost before coming across the Dark Bring; this also demonstrated that its regenerative powers aren't passive and can be activated at will, not "forcing" healing upon the user. The regeneration can take place in various ways, from Hardner's injuries rapidly closing to their almost instantaneous disappearance from sight; during other instances, a foam-like substance was shown to be generated on the wounds, healing them. Hardner's control over Anastasis has caused Hardner to think of himself as immortal, something which he declares consistently.
While offering great advantages, Anastasis does suffer a weakness, as all the power is based on the user's energy: if the user becomes exhausted, the Dark Bring's powers will similarly get weaker, with the user not managing to completely heal himself or to totally restore things. It was this factor, following a long and tiring battle first against Haru Glory and then against Let Dahaka, which caused Hardner's downfall.
Initially portrayed as an intricately elaborated, vaguely egg-shaped medallion, studded with what looked like gems and secured to Hardner's neck by a chain, Anastasis was later given a simpler appearance, taking the form of a large, round gem set into a plain, circular mounting, with four short strips of cloth protruding outwards from its sides in an "X" formation, acting as the clasp for the Captain's cape. "Ἀνάστᾶσις" (Anastasis) is an ancient Greek word which, among other meanings, stands for "Construction" and "Resurrection"; two events which, in a way, the Dark Bring can cause.
- Air Easter: Hardner extends one of his arms outwards and then uses Anastasis to restore the air in the area surrounding him to a clean state. This move was used to get rid of the smokescreen which Haru Glory generated with his Explosion sword. In Christianity, Easter is the recurrence of Jesus Christ's resurrection, something which lives up to the restoring exploited by this technique.
- Forest Easter: A technique which allows Hardner to restore the life of plants in a given area, something which also grants him control over the "resurrected" vegetation, controllable remotely as he wishes. Such plants can be grown at an extreme speed, enough to cover even wide spaces in thick vegetation in mere seconds, generating extremely large trees, which could easily be judged as being centuries-old due to their mass. Hardner can employ such vegetation at his advantage, prompting lianas to sprout from the ground to entangle his foes or grab objects away from him, and similarly using branches of various sizes to restrain, crush or strike them. The Captain is able to use this technique even without calling out its name, which is again a reference to Christian Easter. The plant manipulation is somewhat reminiscent of Jegan's Six Star Dark Bring Yggdrasil.\
- Mass Restoration: Hardner uses Anastasis to completely restore a wrecked building to its former glory. The whole process takes place in mere seconds even if the structure being restored is a gigantic one; all the parts are gathered, generated anew if missing, and the vegetation stemming from years of disuse is removed. This technique was employed by the Captain to reconstruct the Altar of Birth in Makai, following its partial destruction and partial sealing. The Mother Dark Bring is shown to emit intense rays of light in every direction when Mass Restoration is being utilized. A smaller-scale version of this move, which didn't require its name to be called out, was shown performed when Hardner only recreated part of the Altar, following its destruction at Haru Glory's hands.
- Ultimate Pain: A powerful offensive technique which Hardner initiates by grabbing the target and proceeds to restore all the wounds inflicted from the beginning of the target's life. Depending on how much damage received on the target's life, this move is shown to be extremely damaging, causing random excruciating pain which prevents the target from standing back. Hardner made claim that no one ever stood up following such attack, with all those who were subjected to it having died, with Let Dahaka being not only the first one to survive, but also the first one to stand up again to continue fighting. But the damage can be reduced depending on 3 factors: the target's amount of infliction, their durability to resist the pain, and from the user's lack of strength in which not all the wounds can be reopened. This aspect made Haru Glory the second person capable of surviving this technique, due to Hardner having employed it on the Rave Master while he was almost exhausted.
Aside from Anastasis, Hardner was shown employing the Dark Bring Radio Wave, split into two main components, which allows remote long-range communication. One of the pieces consists of a massive dark sphere as the central hub with some wires linked to it, and is located aboard the Albatross; the other's appearance is that of a small earphone-like device, which Hardner is shown keeping on his right ear, right above one of his earrings. The Captain employed this to communicate with Lunar after disembarking the Albatross to summon Endless at the Altar of Birth.
Hardner was shown employing a number of weapons to strike his foes. During his first appearance, the Captain hadn't yet used his Mother Dark Bring Anastasis to restore his left hand and forearm, which were lost during the accident which cost most of the first Blue Guardians' generation their lives, and to his stump was secured a gun, acting like a prosthesis of sort. This consisted entirely of metal and possessed a long barrel secured via a larger semispherical part to a cylindrical section which connected it to the stump. Such firearm fired massive bullets, generating a notably large amount of smoke for its barrel at every shot. The cylindrical part was shown to be concave, housing wires and mechanisms which presumably allowed Hardner to fire it despite no trigger being visible anywhere. It was destroyed by a slash from Yuma Ansect's axe; something which prompted Hardner to regrow his lost limb through the use of Anastasis. After his hand's regeneration, Hardner was shown employing a smaller, handheld firearm to shoot Yuma. This produced a much more reduced amount of smoke, and possessed a smaller barrel, implying it to be of a lesser caliber than the former one.
Executioner's Blade: Hardner's signature melee weapon is the Executioner's Blade, a massive, very long sword fitting the Captain's own size. It possesses a cross handguard, with the central part, bearing a bolt on each side, protruding a bit on the rectangular section connecting it to the blade, a hilt bearing a thin metal section crossing its length vertically, with diagonal lines placed at both sides, a round pommel adorned by a smaller, similarly rounded part on its outer edge. The long blade possesses a light central part and dark cutting edges; right above the hilt, the central section is marked by a rectangular shape with an arched top part, which in it bears a dark, stylized skulls with a pair of tibias crossed below it: such motif is highly reminiscent of the Jolly Roger, a signature symbol of real-life pirates, as a reference to Hardner's own occupation of "air pirate". The most distinctive trait of this already peculiar weapon, however, is its tip: this is shown to be rounded and not sharp, something which doesn't make it fit for performing lunges. This, according to Hardner himself, is due to the weapon not needing it, due to its only purpose being to behead opponents, befitting the Captain's penchant for such practice, and being the namesake of the sword itself. Despite the Executioner's Blade lacking a sharp tip, it remains a highly effective and durable tool, perfectly fitting Hardner's aggressive fighting style, and being resistant enough to shatter rock, as well as to block blows as powerful as the bursts from Haru Glory's Explosion sword without breaking, showing no nicks at all in the process.
Hardner was first shown carrying the Executioner's Blade around after disembarking from the Albatross alongside Belnika to summon Endless. In such instance, he kept the blade secured diagonally to his back, below his cape, its hilt peeping out to the Captain's right from the back part of the latter's collar. The weapon seems to lack a true sheath, not visible anywhere, instead just coming with a hook attached to the Captain's clothing, which, when circling below the sword's handguard, allows Hardner to carry it around on his back.
- He appeared to be very large but has "shrunken" at his first actual appearance.
- Unlike his top underlings, he does not an animal theme.