Acnologia, The Black Dragon and The Dragon King

Acnologia (アクノロギア Akunorogia), also known as The Black Dragon(黒龍, Kokuryū), fearsomely known as The Black Dragon in the Book of Apocalypse, is a powerful dragon in the popular Japanese series, Fairy Tail. It is a dragon that had existed for over 400 years, and is often thought to be one of the beings that is related to Zeref (though in truth he is not). He is one of the series' main antagonists.

Appearance and Abilities

Acnologia's Current Appearance

Acnologia is a gargantuan, massive black dragon with four legs and two wings whose entire upper body is covered in black, round, scales, which in turn are decorated by spiraling, blue markings. His lower body, rather his belly, inner tail, and legs, are grey 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 its chin, is a protrusion that resembles an arrowhead. His large wings are feathery in appearance, similar to that of a bird's and very similar to his fellow dragon, Grandeeney's. The scales disappear at the end of Acnologia's tail, which, in itself, ends in a stinger-like shape.

Before becoming a Dragon in appearance, Acnologia was a normal human. In time, however, Acnologia's appearance turned into that of a dragon due to overuse of his Dragon Slayer magic. In his preferred human form, Acnologia had dark blue hair and the same blue markings across his body that he bore as a dragon. He carried a sharp gaze; his blue eyes have black circles around them. He was also dark-skinned. For clothing, Acnologia dons a high collared, black cloak (which also bears his draconic 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 which are decorated the same as the most former article of clothing. When he lost his left arm to Igneel, he wore a bandage around the stump while in human form.

Acnologia was an extremely powerful dragon, perhaps the most powerful dragon that ever existed in Ishgar. Only Igneel, king of the fire dragons, was able to match him in a physical fight, and even then, Igneel was fighting in a half-dead state. Other than this, only five other dragons, the Five God Dragons of Giltena, such as Mercuphobia, were equals to his power. As Acnologia could eat any type of ethernano particles due to being an Arcane Dragon, he could gain power from any type of magic. Acnologia's specific type of Dragon Slayer magic was unknown, but he was able to steal the souls of almost every dragon he killed or fought, as he did to Igneel, Grandeeney, Metalicana, Skiadrum and Weisslogia. Had Acnologia not stolen the soul of Igneel, it is likely that the Fire Dragon King would have potentially killed the black dragon. Nevertheless, Acnologia came away from the battle badly wounded, as Igneel ripped off the black dragon's arm as Acnologia in turn ripped him in half. As such, Acnologia was by no means invincible. As a former dragon slayer, he was also still prone to motion sickness as a result of his magic combining dragon senses with a human body, and thus he could be rendered incapacitated if put on board a vehicle, such as a ship. Acnologia also eventually proved no match for the strength of Natsu Dragneel, son of Igneel, when Natsu finally faced him for the final time. The Fire Dragon Slayer, armed with the combined might of all his fellow remaining Dragon Slayers, eventually killed Acnologia in combat by destroying his soul.


Before becoming a dragon, Acnologia was a healer and a doctor, and was a gentle, weak soul who wished to become stronger. After becoming a Dragon Slayer and losing his family and city, Acnologia became ruthless, bloodthirsty, and violent. He indiscriminately killed any Dragon he could find regardless if they were his allies or his enemies. He hated all dragons as a result of dragons killing his family, and it drove him to madness.  

When he became a Dragon, he became more reclusive and refused to go into hiding with several of his kind, while at the same time, want nothing to do with humans despite once being a human himself. According to Zeref, Acnologia does not want to interact with humans to which he believes are inferior and considers them annoying insects that are pestering him and would not bother to interact with them. This makes it seem that he is highly arrogant despite the fact he was once human. Upon becoming a dragon, Acnologia decided he wanted nothing less than to drive all other beings to destruction, and proclaimed himself to be the perfect dragon to bring about humanity's extinction. 


Acnologia in his human form.

Born as a human over 400 years ago, Acnologia was among one of the first humans who became Dragon Slayers in which he and his fellow Dragon Slayers would participate in the Dragon Civil War. Originally a doctor living in the city of Montes Secreta, he was friends with a dragon of the same name that later turned on him. Due to evil dragons led by Acnologia I murdering his family, destroying his city, and claiming the life of a child, Acnologia took it upon himself to slay every dragon in existence, deludedly believing they only caused destruction and pain. He and his fellow Dragon Slayers were selected in order to support the side that was desiring coexistence with humans. However, Acnologia and a group of other Dragon Slayers disregarded the cause their comrades fought for, and killed every Dragon they could and bathed in their blood. Wanting the dragons to fear and remember him, but having long since forgotten his true name, Acnologia took the name of his city's former protector, using it to inspire fear in his victims. However, the bloodlust Acnologia awakened within himself could not be sated. Due to the overuse of his magic, Acnologia ended up becoming a dragon himself and as a result declared himself to be the Dragon King.  This event led to the creation of the Festival of the Dragon King, to which it would forever be etched into history. Acnologia's genocide was so utterly successful that most dragons were destroyed by his hand alone. Only the five Dragon Gods escaped his wrath, and of them, only Aldoron, the Wood Dragon God, ever faced him. He was also one of the few dragons to survive a direct encounter with Acnologia. Some people, like Arcadios, the Colonel of Fiore's royal guard, also mistakenly believed Acnologia was connected to Zeref, the black wizard, but in truth, this was not the case, as Acnologia was only drawn to Zeref because the black wizard caused so many negative emotions around him and because Acnologia was attracted to strong magic power out of a desire to fight potentially worthy opponents.

For many years, Acnologia roamed Earth Land, while he became recognized as a fearsome dragon, and was responsible for his single-handed destruction of an entire continent. At some point in time, he encountered Gildarts Clive, the ace and strongest wizard of Fairy Tail as the latter was going on his "100-year quest" on Zonia Mountain. In an instant, Acnologia attacked and successfully mutilated Gildarts to which he lost his left arm, left leg, and an unspecified organ. Acnologia left him to die and flew off but unknown to him, Gildarts survived the onslaught and became credited for being the first human being who ever survived Acnologia's wrath and lived to tell the tale.


Tenrou Island arc

Acnologia heads to Tenrou Island

After Zeref appeared on the Grimoire Heart Ship and killed Hades, Acnologia arrives on Tenrou Island where the Fairy Tail mages were taking their S-Class exams and begins to unleash destruction. As the Black Dragon was rampaging across the island, Makarov who sensed its destructive capabilities, entered into his Titan mode and tried to hold the Dragon at bay while telling his guildmates to run and leave the island. However as the Black Dragon gained the upper hand and was about to launch a fatal blow after pummeling the elderly Guild Master, Natsu decided to fight Acnologia together with Makarov.

Fairy Tail Vs. Achnologia

Despite this interference, Acnologia tried to get rid of Natsu but he stayed latched onto its back.  The others led by Erza followed suite and everyone began to attack the massive black Dragon. Despite the combined teamwork of all the Dragon Slayers and the mages, it was not enough to defeat the dragon as Gildarts noted that it was toying with them rather than going at the level of strength it did when it fought Gildarts. The Dragon flew into the air and charged its Dragon Roar, and when fully charged unleashed a tremendously powerful blast that seemingly destroyed Tenrou Island and all of the Fairy Tail mages. After the deed was done, Acnologia flew once again into the distance and seemingly disappeared without a trace.

Tartaros arc

The Black Dragon reappears once more

Acnologia appears once again as Fairy Tail and Tartarus battle one another on the Cube, in the ruins of Taratarus' headquarters. As he gets to his destination, the mages and demons take notice to which the Dragon Slayers react by having their hearts beat faster and stay motionless but awake. Acnologia as he flies to his destination, charges his Dragon Roar and lays waste to the landscape below him which led to a series of explosions. When Acnologia arrives he flies right past the Fairy tail mages and create a shockwave all around them, much to their despair. When Acnologia stops, Mard Geer, the Underworld King of Tartarus notes about why Acnologia is here and guesses that Acnologia came for E.N.D as he belives that Acnologia fears the demon too. As Acnologia charges its Dragon Roar, Igneel who has been hiding inside of Natsu this whole time emerges with the intent on stopping the apocalypse. Following Igneel's appearance, he flies and tackles the black dragon in order to stop the apocalypse. As the battle continues, Igneel attacks Acnologia with a large fire blast in which it engulffed the black dragon in a large explosion only for it to emerge 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 continued 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 to higher altitude 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 badly 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 Face Bombs.

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, too wounded to continue his attack.

At some point, Zeref watched Acnologia travel through a barren wasteland, where Acnologia was quick to catch a pink ribbon that was once the powerful relic known as the Dragon Cry Staff. Upon touching it, Acnologia was shown the memories of his past; he had sworn to kill all dragons in vengeance for their "murder" of Sonya, the little girl he failed to save. He was shown having killed Zirconis and another dragon, as well as nearly killing Animus, who saved himself and the girl by hiding inside Sonya's soul. As Acnologia reflected on the memories, he regarded them as nonsense and turned the ribbon to ash, before continuing on his way.

Alverez Empire Arc

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.

Still residing in the cave where he and Zeref conversed last, Acnologia mentions that where his stolen arm was still hurts; adding that he will destroy everything at the Dragon King Festival, he gets up and changes into his Dragon form, after which he shouts that he is the true "Dragon King". As he proclaims his supremacy, a strange, 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 on Ishgar, just outside the borders of Bosco during the war between Zeref's Alvarez Empire and Ishgar. There, he stands before three of Zeref's 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 reveals his motive, stating 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.

Acnologia begins his trek to the northern battlefield at Zonia; along the way, he senses Gajeel's "death" and declares that only six Dragon Slayers remain, however, he is intercepted by Irene Belserion, whom he tries to dismiss. The Spriggan 12 member instead opts to block his path, prompting Acnologia to question her knowledge of him and wonder aloud whether she can even put up a fight against him. Acnologia is almost immediately struck with a high-level enchantment from Irene (the Magic of which he recognizes, as she was the one who made him a Dragon Slayer); although taken aback at first, after realizing that Irene is a High Enchanter, he becomes excited and enthusiastically attacks her, in turn, with his Dragon Slaying Magic. After the dust settles, Acnologia praises Irene for her skill, but after Irene praises Acnologia for his power as well, she insinuates that Zeref will be more powerful than him once he attains Fairy Heart. The Dragon King and the Spriggan 12 member then briefly bicker back and forth until Irene decides that she is going to end Zeref's "game" of a war by utilizing a type of Magic that even Acnologia doesn't recognize. Irene informs him that it's a new type of Magic, and that she is enchanting the land of the entire Kingdom of Fiore; Acnologia asks for Irene's name, and after he is given it, he, and the entire kingdom, are enveloped in the light of Universe One. As a result of this, Acnologia is warped somewhere far away from the shrunken landmass of Fiore.

Much later on, with Irene lying dead from her battle with her daughter, Ezra Scarlet, the effects of Universe One fade off, marking Acnologia's return. Wasting no further time, Acnologia notices Irene's body, approaching her. As he comments on her being the one who gave the power of Dragon Slayer Magic to humanity, Acnologia sadistically stamps on her corpse continuously to express his resentment for what she did to him, laughing all the while. His attention then turns to Wendy Marvel and and Erza, and decides to try and attack them, as he is still intent on killing all dragon slayers. However, the Wizard Guild Blue Pegasus intervened, ramming and stunning him with their flying magic bomber, the Christina Advanced.

After the Alvarez Empire is defeated and Zeref dies, Fairy Tail and their allies attempted to imprison Acnologia within a space-time rift discovered by Lucy's ancestor, Anna Heartfilia. During the chase, Erza also caught on to Acnologia's weakness of motion sickness in order to keep him at bay. But when Acnologia is sucked into the rift, he is instead empowered by the rift's properties and escapes, while his disembodied soul traps all of the present dragon slayers in the rift to maintain his new, immeasurable power while he rampages across the nation. After Lucy and the other wizards immobilize the dragon's body within the spell Fairy Sphere by way of body link magic and through use of a boat to keep him incapacitated, Natsu, having finished his battle with Zeref and seeking to avenge Igneel's death at Acnologia's hands, accumulates the other dragon slayers' magic and destroys Acnologia's soul, killing him and freeing the dragon slayers from captivity in the space-time rift. Acnologia then disintegrates as he dies, saying that Natsu is the superior fighter and truly worthy to be the king of the dragons (which Natsu dismisses, as he has no interest in being called such). With Acnologia finally dead, the last of the dragons of Fiore finally fade into extinction, leaving only the seven Dragon Slayers left as the legacy of the once mighty race in that kingdom.