Acnologia

"I shall devour all. I am the True King of all Dragons! I am Acnologia!"

- Acnologia

"It doesn't matter where you stand, i'll destroy you, then i'll destroy them and the ENTIRE WORLD!!!!!"

- Acnologia before killing Igneel.

Acnologia also known as The Black Dragon, and fearsomely reputed as The Black Dragon in the Book of Apocalypse, is the secondary antagonist of the manga/anime series, Fairy Tail. He is a incredibly powerful Dragon Slayer that can take the form of a Dragon and is the self proclaimed King of the Dragons. He has succeeded in killing all the Dragons and is now hunting down the last remaining Dragon Slayers.

He is voiced by Kōsuke Toriumi in the Japanese version of the anime and J. Michael Tatum in the English version.

Appearance
"He continued to destroy Dragons and bathe in their blood. Presently, his skin turned to scales, his teeth to fangs. He transformed into a Dragon himself. A Dragon with pitch-black wings unlike any other Dragon."

- Zirconis explaining Acnologia's transformation

Acnologia is a mastodonic dragon whose entire upper body, is covered in black, round scales, which in turn are decorated by spiraling, blue markings. Its lower body, specifically its belly, inner tail and legs, is grey in color, and seems to be rather smooth. It possesses a blunt, rounded head with four large and elongated plates extending backwards, and has white beady eyes. Its mouth is full of sharp teeth, and below it is an elongated protrusion pointing downwards. Acnologia’s gargantuan, multi-layered wings are composed of the very same plates covering its whole body, which take on a formation reminiscent of a bird’s feathers. Its massive tail splits in two at its end, where the black plates disappear, and takes on a double stinger-like appearance.

In his human form despite being 400 years old has the appearance of a muscular young man with long dark blue colored hair. His eyes have black circles around them and he bears the same light blue markings as he does in his Dragon form. For attire he dons a high collared black cloak and has a necklace of red dragon claws around his neck and a sash around his waist. He wears a gold ring on his left arm and baggy pants that are decorated the same as the former article of clothing.

After his battle with Igneel his right arm was taken, in his Dragon Form it has regenerated but in his Human Form it is still missing so he keeps his missing arm under his cloak.

Personality
"He refuses to speak to them which means he views them as nothing more than insects, Men don't engage vermin in conversation this is no different, and men certainly don't battle pests the same as actual threats."

- Zeref during Acnologia's rampage.

While other Dragons appear somewhat amicable to humans, Acnologia is extremely inimical and malevolent towards them, so he perspectively scrutinizes them as infinitesimal. Zeref words it, "it sees them as nothing more than insects pestering him". 400 years ago, Acnologia was a ruthless, aggressive, bloodthirsty, detrimental, sarcastic, and a violent person. In his dragon form he shown to be very destructive and violent as described in legend. Acnologia also has a love for battle against opponents who can challenge his own power and strength. In his human form Acnologia has a stoic and composed personality even after slicing God Serena's abdomen open he is still composed. It's also been said that Acnologia has a fear of Zeref's most powerful Demon, E.N.D.

History
Prior to the beginning of the series, he was born as a human over 400 years ago. He was originally one of the first Dragon Slayers during the Dragon Civil War to support the coexistence of both humans and dragons. Unfortunately, Acnologia and other Dragon Slayers turned against their own dragons, killed them, and bathe in their blood. Originally believed to be done from the aid of Zeref, Acnologia physically turns into a dragon, and proclaimed himself to be the Dragon King. This event was forever etched into history as the Festival of the Dragon King.

For many years, Acnologia terrorized and was feared by the people of Earth Land, as he was credited with the single-handed destruction of an entire country. At some point of time, Acnologia ran into Gildarts Clive when the 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, though Gildarts managed to survive, albeit with difficulty.

Tenrou Island arc
Acnologia comes to Tenrou Island, wreaks havoc on it, and fights the Fairy Tail members on the island. In the battle, it causes so much devastation that Makarov is forced to hold him off to allow the other Fairy Tail Mages to escape. As the two fight, Acnologia is eventually able to knock Makarov to the ground. Just as it is about to kill Makarov, all of Fairy Tail comes back and starts attacking the dragon. Acnologia then flies into the air, and seemingly destroys Tenrou Island, and all the Fairy Tail members on it with his Dragon's Roar.

After these events, Acnologia takes back up to the skies and disappears from sight.

Tartaros arc
Acnologia appears one more time at the ruins of Cube where the battle between Fairy Tail Mages and Tartarus takes place. As he nears his destination, both Mages and the Demons take notice of his presence.

Acnologia appears one more time at the ruins of Cube where the battle between Fairy Tail Mages and Tartarus 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 an 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 Flame 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.

Avatar 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 questions what Zeref wants, however he is met with inquisition, as Zeref points out that Acnologia could rule the world with his power if he wished, calling his motives unfathomable, though Acnologia also says the same of Zeref's motives. Acnologia then listens as Zeref tells him that he will not join or fight against him; rather, he will kill him along with everyone else in the world and fathoms that Acnologia has been waiting for someone to give him a true challenge and states that he will gladly take on the role of that challenger. 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. He is then intercepted by another one of the Shields of Spriggan named Irene. He tells her to move but she refuses so they fight. The 2 stare each other down then Irene uses her magic to create a orb of fire which surprises Acnologia who quickly puts up a defense but is blown away. Catching himself, Acnologia notes that must be an enchanter before retaliating as his own magic erupts from the ground creating a large crater. It causes Irene to leap in the air, after acknowledging his strength, Irene ponders on what Acnologia once Zeref obtains Fairy Heart and uses it against Acnologia. He then asks Irene if she believes Zeref has the power to defeat him as she states he will. She then uses magic that Acnologia surprised that he is unfamiliar with as Irene states it's Magic of the new era. He then asks if she enchanted the Earth but she says only the country of Fiore. She used a Spell that enveloped the entire Kingdom of Fiore called Universe 1. He then asks her name she reveals herself as one of the Spriggan 12 and she wishes to see Acnologia again before disappearing. As a result, Acnologia was warped somewhere far away from the shrunken landmass that is Fiore.

Powers and Abilities
"Many years ago, Acnologia used his Dragon Slayer Magic to tear our souls from our bodies."

- Grandeeney explaining how her soul was stolen

Dragon Slayer Magic: As one of the first humans who entered the Dragon Civil War, Acnologia was also among the first Dragon Slayers brought into existence. Over time, however, as he slayed many Dragons until, he himself was turned into a Dragon due to the extensive overuse of his Lost Magic. While it is currently unknown exactly which element Acnologia employs in his casting of Dragon Slayer Magic, it grants him the ability to reap the very souls of Dragons, leaving them in a half-dead state. Dragon Form: Acnologia, contrary to the legends surrounding him, did not entirely became a Dragon and has retained the ability to enter and exit his extremely powerful Dragon Form at free will. Immense Strength: Acnologia holds tremendous raw strength even in his human form, as showcased when he slayed God Serena, the infamous strongest Mage of Ishgar himself and a Shield of Spriggan, with a single bare hand alone, ripping right through his abdomen and killing him in one swipe almost instantly.
 * Dragon's Roar: Like all Dragons and Dragon Slayers, Acnologia can perform a Dragon's Roar, incorporating his respective element into a massive breath attack. While, as mentioned, which element Acnologia employs is currently unknown, said blast, while he was a Dragon, was potent enough to "completely eradicate" the entirety of Tenrou Island and imprint a giant crater into the ocean.
 * Flight: As a Dragon, 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.
 * Enhanced Durability: Acnologia, while a Dragon, is capable of shrugging off attacks from extremely powerful Mages like Erza Scarlet, Laxus Dreyar, and Mirajane Strauss, as well as from Natsu Dragneel, Gajeel Redfox, and Wendy Marvell, the latter three using their Dragon Slayer Magics, all their Magics having absolutely no effect on the Black Dragon. Later on, it is shown how even other Dragons of Igneel's caliber have high difficulty harming Acnologia in any noteworthy way, him taking the full force of Igneel's massive fire breath attack and emerging unscathed as if nothing happened.
 * Enhanced Strength: Given his immense size, Acnologia, in Dragon form, is easily capable of reducing a substantially sized area to rubble by simply landing on top of it. Truly attesting to the form's immense brutish strength, Acnologia engaged in a head-on physical confrontation with Makarov in his Giant form and easily gained the upper hand. According to Gildarts Clive, despite the amazing physical feats Acnologia performed on Tenrou Island, the Dragon wasn't using the same level of strength as he was during their brief confrontation, that rather, the Black Dragon was toying around with every last one of them.

Immense Speed: While only in his human form, Acnologia has been shown to move at blinding speeds, striking down God Serena before he or his spectating fellow Shields of Spriggan, August and Jacob Lessio, even knew what had happened.

Enhanced Smell: Acnologia has an incredible sense of smell, which he shares with other Dragon Slayers. He could instantly tell God Serena was a Dragon Slayer after smelling him from a distance and could tell there were seven other Dragon Slayers across the whole country Fiore, despite the incredible distance between all of them.

Manipulation Immunity: According to Future Rogue, Acnologia is immune to Dragon Supremacy Magic.

Immense Magic Power: While only in his human form, Acnologia's Magic Power was said to be overwhelming to the point of even members of the Wizard Saints and Spriggan 12, even the strongest male, "Magic King" August himself, being awed and sweating at his enormous power. The strongest female member of the Spriggan 12 Irene Belserion even stated that he was more powerful than she initially thought. August even said that Zeref could only face him with the Fairy Heart's power. Much stronger than initially assumed to be, even after apparently going toe-to-toe with Igneel, the "Fire Dragon King", in combat (although Igneel's power was quickly dwindling due to the years he was sealed), Acnologia is mentioned by Zeref to be still waiting for someone to truly challenge him, implying that he was possibly holding back in his bout with the Fire Dragon King. Additionally, Zeref at one point has stated that Acnologia could rule the world with his power (which he was able to do in Future Rogue's timeline).

Major Battles

 * Dragon Civil War
 * Fairy Tail vs. Acnologia (Win)
 * Igneel vs. Acnologia (Win)
 * Irene Belserion vs. Acnologia (Stalemate due to interference)

Trivia

 * Although he is only the secondary main antagonist, he is the most powerful antagonist in the series.
 * It is currently unknown what Dragon Slayer Magic element he casts.
 * Acnologia is the only Dragon Slayer to have transfom into a Dragon.
 * Fan's have speculated that Acnologia's Dragon Slayer Magic element is Etherion.