|Human | Dragon|
|Base of Operations|
Acnologia (アクノロギア Akunorogia), also known as The Black Dragon (黒龍 Kokuryū), and fearsomely reputed as The Black Dragon in the Book of Apocalypse, is a cataclysmically powerful human being that can take the form of a Dragon that assaulted the Fairy Tail Mages on Tenrou Island in the Year X784.
Human | Dragon
As a Dragon, Acnologia is mastodonic, and has an entire upper body covered in black, round, scales, which, in turn, are decorated by spiraling, blue markings. His lower body, specifically his chin, chest, stomach, inner tail, thighs, and arms, are gray in color, and appear to be rather smooth. Acnologia's eyes are white and beady, and his head is round and blunt with four, large, elongated plates extending backward. Acnologia's mouth is full of razor-sharp teeth, and, attached to his chin, is a protrusion that resembles an arrowhead. His large wings are feathery in appearance, akin to a bird's, and very similar to fellow Dragon Grandeeney's. The scales disappear at the end of Acnologia's tail, which, in itself, ends in a stinger-esque shape.
Acnologia's preferred appearance is that of his human form, which is that of a rather muscular young man with long, dark blue colored hair. He carries a sharp gaze; his eyes have black circles around them. He is dark-skinned, and on his body he bears the same light blue markings he does when he is a Dragon. For attire, Acnologia dons a high collared, black cloak (which also bears his draconian markings), sharp red claws around his neck, a sash around his waist, a gold arm ring tightened around his right upper arm, and baggy pants that are decorated the same as the most former article of clothing.
Four hundred years ago, Acnologia was a ruthless, bloodthirsty and violent person. He killed any and all Dragons he could, ignoring the fact that many were his comrades.
In the present, Acnologia is a recluse who wants nothing to do with humans, in spite of the fact that he is one. As Zeref puts it, he sees other humans as nothing more than insects, ignoring any and all attempts by them to converse, which suggests that Acnologia is highly arrogant. However, inversely, Acnologia's motives are also shrouded in mystery, as even with one arm he, according to Zeref, has the power to rule the world yet elects not to do so. Insights into his wishes have only been touched upon by outside sources, which include his vague desire to fight against humanity, as well as face an opponent strong enough to give him a real challenge. Ultimately, in a form of irony, despite his inherent hatred for humanity, Acnologia prefers to take on the shape of his old human form in casual instances.
Born over 400 years ago, Acnologia was one of the first Dragon Slayers to come into being, entering the Dragon Civil War on the side supporting coexistence. Acnologia and a group of other Dragon Slayers, however, disregarded the cause their comrades fought for, and killed every Dragon they could, bathing in their blood. Due to the overuse of his Magic, Acnologia's physique eventually turned into that of a Dragon's, and he proclaimed himself to be the Dragon King. This event was forever etched into history as the Dragon King Festival.
For many years, Acnologia roamed Earth Land, reputed as a fearsome Dragon, and was credited with the single-handed destruction of an entire country. At some point in time, Acnologia ran into Gildarts Clive when the S-Class Mage was on his "100-year quest" on Zonia Mountain. In an instant, Acnologia took Gildarts' left arm, left leg, and an unspecified organ, leaving him to die, before flying away. Gildarts, however, managed to survive, albeit with difficulty, leaving him as the first human to ever see Acnologia and live to tell the tale.
Tenrou Island arc
Seemingly beaconed by Zeref, Acnologia arrives on Tenrou Island, wreaking destruction in his wake. Sensing the destructive capabilities the Black Dragon possesses, Makarov enters Giant Mode, attempting to hold the Dragon at bay to allow the other members of Fairy Tail to escape. After a brief struggle, Acnologia, taking advantage of Makarov's previous injuries, knocks the Guild Master to the ground, pummeling him with his claws.
Just as he is about to kill Makarov, Natsu latches onto Acnologia, preventing the killing blow. Despite Acnologia's attempt to rid himself of Natsu, the Fire Dragon Slayer remains latched onto the Black Dragon's scales, demanding that he leave their Master alone. Led by Erza, the other members of Fairy Tail return, aiding Natsu in his assault against the Dragon. As Gildarts notes that Acnologia is simply toying with them all, the Dragon flies into the air, and then proceeds to seemingly obliterate Tenrou Island with his Dragon's Roar. After the deed is done, Acnologia soars off into the distance.
Acnologia appears one more time at the ruins of Cube where the battle between Fairy Tail Mages and Tartaros takes place. As he nears his destination, both Mages and the Demons take notice of his presence. Effortlessly, Acnologia creates huge explosions with his breath, as well as shockwaves with his wings alone, much to the Mages' despair. He approaches Mard Geer and the Demon deduces that the Black Dragon is after E.N.D. However, Acnologia's rampage is temporarily interrupted, as Igneel, released from within Natsu's body, attacks him, with an intention to stop his rampage. Acnologia and Igneel begin to clash, while all the Mages below watch in horror and awe. After Natsu jumps on Igneel, the latter fires a huge flame blast towards Acnologia, although the beast easily shrugs off the attack and comes out of it unscathed. Acnologia is then later punched by Igneels' version of Fire Dragon's Iron Fist, however he shrugs this attack off as well.
Shortly thereafter, taking advantage of Igneel's worry for Natsu, Acnologia fires a Dragon's Roar at his opponent's head, but misses. Acknowledging Igneel as his enemy, Acnologia speaks to him, citing his displeasure at the existence of Dragons; he ends his comment by saying that he will slay Igneel. As the fight goes on, Acnologia tells Igneel that he won't escape. However, the latter explains that he didn't intend to run, and that he moved so that he can fight without holding back, in order to defeat the other creature. Acnologia, however, says that it won't be a simple defeat, but a one-sided obliteration. Later as the Face bombs across the continent begin to detonate, Acnologia is sent plummeting towards the earth extremely wounded, much to everyone's surprise. His body is then used as a victory stand by Igneel, who announces the arrival of the other Dragon Slayers' foster parents to stop the mighty threat of the Magic Pulse Bomb.
Acnologia doesn't stay down for long though, as he slashes out at Igneel and takes their battle back up into the sky. There, he questions Igneel's motives for having the other Dragons hide inside their foster Dragon Slayer children, and, when Igneel asks if he is scared of E.N.D. reviving, berates the Fire Dragon and declares that all he wants is utter destruction. Acnologia quickly overwhelms Igneel and repeatedly crushes his torso with his claws whilst screaming about destruction; he also derides the Dragon for being the Fire Dragon King yet not being able to fight equally with him and continues his relentless assault. Acnologia is then quickly overtaken by Igneel and loses his left arm, however in return, Acnologia destroys nearly the entire left half of Igneel's torso and then kills him with his Dragon's Roar. With his arm gone and his target slain, Acnologia then leaves Magnolia.
One year after losing his arm to Igneel, Acnologia accepts Zeref's proposal to meet, and does so at an undisclosed rocky terrain, albeit in his human form instead of as a Dragon. Acnologia asks what Zeref wants; however, he is met with curiosity, as Zeref points out that Acnologia could rule the world with his power if he wished, calling his motives unfathomable. Acnologia, however, says the same of Zeref's motives. He then listens as Zeref tells him that he will not join or fight against Acnologia; rather, he will kill Acnologia along with everyone else in the world. He further implies that Acnologia has been waiting for someone to give him a true challenge and Zeref claims that he will gladly take on the role of challenger for Acnologia. Acnologia then gives a sly grin as Zeref tells him to wait for the ultimate clash between human, Dragon, and immortal to approach.
Alvarez Empire arc
Still residing in the cave where he and Zeref conversed last, Acnologia mentions that where his stolen arm was hurts; adding that he will destroy everything at the Dragon King Festival, he gets up and takes on his Dragon form, after which he shouts that he is the true "Dragon King". As he proclaims his supremacy, however, a shadow-like substance extends from where his left arm used to be.
Acnologia, in his human form once again, later appears at the eastern war-front, just outside the borders of Bosco. There, he stands before three Shields of Spriggan—Jacob Lessio, August and God Serena—the latter having just ended his battle against the remaining Gods of Ishgar, as well as Jura Neekis. Claiming that he can quite clearly smell the stench of a Dragon, Acnologia challenges God Serena, with the Shield of Spriggan seemingly over the moon about finally encountering the "Dragon King". Before God Serena can finish his rant about how difficult it had been to find him, Acnologia suddenly attacks, tearing a hole in the side of his stomach with a single swift swipe of his hand. As the surrounding Mages watch on in awe, Acnologia proceeds to casually walk away from the scene, leaving the collapsed body of God Serena behind. As he takes his leave, he states that there are still seven more Dragon Slayers left, indicating that he intends to annihilate each and every one of them, until all remnants of the Dragons have been wiped out of existence.
Magic & Abilities
Dragon Slayer Magic (滅竜魔法 Metsuryū Mahō): As one of the first humans who entered the Dragon Civil War, Acnologia was also one of the first Dragon Slayers brought into existence. Over time, however, as he slayed many Dragons, he himself was, eventually, turned into a Dragon due to the overuse of his Lost Magic, though he retains the ability to shift back into human form at will. It is currently unknown exactly which element Acnologia employs in his casting of Dragon Slayer Magic, however his Dragon Slayer Magic grants him the ability to reap the souls of Dragons, leaving them in a half-dead state.
- Dragon's Roar: Like all Dragons and Dragon Slayers, Acnologia can perform a Dragon's Roar, incorporating his respective element into the attack. While which element Acnologia employs is currently unknown, the blast was powerful enough to "completely eradicate" Tenrou Island and imprint a giant crater into the ocean.
Flight: In his Dragon form, Acnologia possesses the ability to fly, using his large wings to travel great distances, maneuver high up in the air, and perform aerial assaults on those below him.
Immense Durability: Acnologia is capable of shrugging off attacks from very powerful Mages, such as Erza Scarlet, Laxus Dreyar and Mirajane Strauss. Even attacks from Natsu Dragneel, Gajeel Redfox, and Wendy Marvell, who all employ Dragon Slayer Magic, the Magic that is renowned for its legendary ability to slay Dragons, had absolutely no effect on Acnologia. Not even attacks from Dragons can harm Acnologia as shown with the Black Dragon taking the full force of Igneel's massive fire breath attack and emerged unscathed as if nothing happened.
Immense Strength: Given his immense size, Acnologia is easily capable of reducing a substantially-sized area to rubble by simply landing on top of it. As a testament to his immense strength, Acnologia can engage in a head-on physical confrontation with Makarov in his Giant form and easily gain the upper hand. According to Gildarts Clive, despite the amazing feats Acnologia performed on Tenrou Island, the Dragon wasn't using the same level of strength as he was during their brief confrontation. Rather, Gildarts noted that the Black Dragon was toying around with every last one of them. Acnologia is also much stronger than he is assumed to be, as even after apparently going toe-to-toe with Igneel in combat, Zeref comments that Acnologia is still waiting for someone to give him a true, challenging fight, implying that he was possibly holding back in his bout with the Fire Dragon King. Zeref has also stated that Acnologia could rule the world with his power, yet elects not to for whatever reason. As a testament to the aforementioned great power, Acnologia, in his human form, slew God Serena, the infamous strongest Mage in Ishgar and Shield of Spriggan, with his bare hands, ripping right through his abdomen and killing him almost instantly.
Immense Speed: While only in his human form, Acnologia has shown to move at blinding speeds as he struck down God Serena before he or his fellow Spriggan even knew what happened.
Shapeshifting: Acnologia, contrary to the legends surrounding him, did not entirely transform into a Dragon and has retained the ability to enter and exit his human form at will.
Immense Magic Power: Upon arriving to the battlefield while only in his human form, Acnologia's Magic Power was said to be overwhelming to the point when even members of the Wizard Saints and Spriggan 12 were awed at his enormous power. August even said that Zeref could only face him with the Fairy Heart's power.
- (To Igneel) "I recognize you as my enemy, Dragon. And I shall slay you." 
Battles & Events
|Dragons||Acnologia • Atlas Flame • Dark Dragon • Grandeeney • Igneel • Levia • Metalicana • Motherglare • Rock Dragon • Scissor Runner • Skiadrum • Weisslogia • Zirconis • Zirconis (Spirit)|
|First Generation||Acnologia • Gajeel Redfox • Natsu Dragneel • Wendy Marvell|
|Second Generation||Erik • God Serena • Laxus Dreyar|
|Third Generation||Future Rogue Cheney • Rogue Cheney • Sting Eucliffe|