I am vengeance incarnate! I am Nidhogg! Thou shall die by my hand!
Nidhogg is one of the seven wyrms born of Midgardsormr, said to have long terrorized Coerthas since Ishgard's founding, using the Dragonsong to rally the Dravanian Horde to war the past thousand years.
Nidhogg is a black dragon with leathery wings and jagged scales. He has four narrow horns facing outward, and combined with the shape of his maw give a fierce appearance.
He is initially seen with a single yellow eye in the right socket. It was later revealed the eye was borrowed from Hraesvelgr after his were taken by King Thordan I's knights. His true eyes are red with a dark aura emanating from them.
Nidhogg is so consumed with rage over the betrayal of King Thordan (and, as it is heavily implied, at what happened to his other siblings at the hands of the Allagans) that he intends to break the Holy See of Ishgard through a millennium-long war. This rage transcends both through his eyes—leaving the Azure Dragoon vulnerable to the great wyrm's emotions—and in his Dragonsong, which drives his brood to not only attack the Holy See, but even causes them to attack Hraesvelgr's brood for not being utterly devoted to Nidhogg's crusade.
Nidhogg refuses to accept or even comprehend the possibility of peace between Ishgard and dragon-kind. Thus, he sees any negotiation attempt foolish and any dragon desiring peace a traitor, and is willing to murder members of his own kind in pursuit of his vengeance. Even his father, Midgardsormr, laments on how far Nidhogg has fallen as a result of his wrath. Nidhogg believes his vengeance is eternal and looks upon every challenger with contempt, refusing to believe in the possibility of defeat. This likely resulted in his original defeat that cost him his eyes.
Upon his final defeat at the hands of the Warrior of Light, Nidhogg's spirit appears serene, likely finally feeling free from his anger and hate.
Being a Great Wyrm, Nidhogg can rally the entire Dravanian Horde using Dragonsong, usually against his arch-enemy, the Holy See of Ishgard. This Dragonsong even awakens his father's spirit within the The Keeper of the Lake, who had remained dormant since the Battle of Silvertear Skies.
Nidhogg's abilities surpass those of ordinary dragons, and Ser Alberic Bale implies he has some measure of psychic influence on mortals. The removal of "the Eye" from Haldrath a millennium ago greatly weakened him, and it is said that if Nidhogg were to regain it, no magical wards would be able to save Ishgard from his fury. Some believe that Hraesvelgr is Nidhogg's only equal.
Twelve hundred years ago, the Ishgardians and the dragons forged an alliance based upon the example of Hraesvelgr and Saint Shiva. Only Nidhogg believed there could be no peace between their kinds, viewing mortals as untrustworthy after what happened to Bahamut and Tiamat.
His concerns appeared unfounded for two hundred years, until the Ascians revealed to King Thordan I the source of the dragons' powers lay within their eyes. This led to Thordan killing Nidhogg's sister, Ratatoskr, and he and his knight ate her eyes to obtain their power. A furious Nidhogg slew Thordan, but was defeated by his son Haldrath, who plucked the dragon's eyes from his head. While this would normally kill a dragon, Nidhogg mustered the strength to reach the palace of Zenith and tell his brother, Hraesvelgr, of what had transpired.
Nidhogg blamed Hraesvelgr for giving the mortals—if indirectly—the opportunity to slay Ratatoskr, and coerced him into relinquishing one of his eyes to him. Intending to slaughter those of the Ishgardian bloodlines who remain loyal to their faith, Nidhogg continued to wage his war of vengeance for the next 1000 years, entering periods of deep sleep for portions of the conflict as his kind normally does. The Holy See whitewashed history to make Nidhogg appear to have attacked Ishgard unprovoked, claiming Thordan and his twelve knights faced the dragon in a battle that lasted a week that claimed the lives of both the king and six of his men. The story was designed to conceal the Holy See possessing both of Nidhogg's eyes: the right eye buried with Haldrath, while the left is used by the Azure Dragoon, the current being Estinien Wyrmblood. The Ishgardians inherit Ratatoskr's power and mutate into dragon-like creatures when exposed to dragon's blood.
Nidhogg awakens and rallies the Dravanian Horde to renew his war on Ishgard with the support of Ysayle whose heretics disable the outermost ward of Daniffen's Collar. The initial assault fails when Nidhogg's champion, Vishap, is slain by the Warrior of Light at the Steps of Faith as it tries to dismantle the rest of the wards.
Wicked mortals! I shall melt your flesh, and turn your bones to ash!
Nidhogg's full story is revealed to the Warrior of Light and Alphinaud Leveilleur as they, Estinien, and Ysayle journey to Dravania to parlay with Horde. Hraesvelgr explains that Nidhogg will never accept the terms of peace, while revealing how far his brother would go to destroy Ishgard's people.
When Nidhogg senses the death of his consort, Tioman, he recalls his forces to the Aery as he expects an assault on his domain. Nidhogg gives the Warrior of Light and Estinien a not-so warm welcome to his abode, pursuing the latter to reclaim his eye. Estinien removes Hraesvelgr's eye from Nidhogg with the dragon's body exploding into mist. The Warrior of Light receives visions of what truly happened the day Nidhogg lost his eyes.
At the bottom of the Aetherochemical Research Facility, the Warrior of Light uses the left eye of Nidhogg to eradicate the Ascian Igeyorhm after trapping her in White Auracite. Archbishop Thordan VII retrieves the right eye from Haldrath's coffin, and uses it to transform into King Thordan of the Knights of the Round. After King Thordan has fallen, Estinien congratulates the Warrior of Light for stopping the archbishop while retrieving Nidhogg's other eye. Before Estinien can hide the eyes away, Nidhogg's spirit consumes the Azure Dragoon's mind while using his body to regain a physical form. The reconstituted Nidhogg flies away to the dismay of Midgardsormr, as he fears his offspring will renew war on man, and he wonders what the endless quest for vengeance has turned Nidhogg into.
Child of Dravania! Art thou grown so forgetful that thou wouldst forsake kith and kin, and consort with the spawn of Thordan? That thou wouldst dare contemplate peace! Hearken unto me, all of you! The final chorus is nigh, and all will be held to account! All will bathe in the flames of retribution!
A peace summit is held by Aymeric de Borel between Ishgard and Dragon at Falcon's Nest. Having full control over Estinien's body with his eyes fused on the dragoon's mail, Nidhogg interrupts the proceedings and impales the dragons' representative, Vidofnir, while denouncing her as a traitor to dragon-kind. Nidhogg denounces any form of peace as long as he lives, while declaring that he and his brood will soon have a final reckoning with the Ishgardians. Nidhogg assumes his true form and flies off. As he only wounded Vidofnir without killing her, Nidhogg's warning of the Dragonsong War's final battle is hinted to be directed towards both the Ishgardians and Hraesvelgr's brood should they still consider to ally themselves with the Elezen.
As Aymeric, Alphinaud, and the Warrior of Light convince Hraesvelgr to fight with them, Nidhogg attacks the Steps of Faith and defeats his brood-brother. He is caught off guard in discovering that Hraesvelgr had transferred one of his eyes into the Warrior of Light, and loses to the Warrior in battle. Though Estinien pleads the Warrior to kill him to slay the wyrm, the Warrior of Light and Alphinaud rip the eyes off of the dragoon with help from the ghosts of Ysayle and Haurchefant Greystone. Rendered incorporeal, Nidhogg's spirit fades away while his eyes are cast off into the abyss below the Steps of Faith.
Nidhogg's eyes are recovered by the Warriors of Darkness who relinquish them to the Ascian Elidibus who presents the eyes to the Ala Mhigan extremist the Griffin, who uses them to fuel the summoning of Shinryu. The Eyes form Shinryu's core but are eventually depleted of their power once the primal is destroyed during the liberation of Ala Mhigo. Estinien, appearing to have trace elements of Nidhogg's power, destroys the powerless eyes and finally puts an end to Nidhogg's legacy of terror.
The Warrior of Light reunites with Alberic and Orn Khai following their journey in the First. Upon hearing of Andreia's demise, the group is reminded of Nidhogg, who was also driven by the past. Orn Khai laments that no one would mourn Nidhogg, and decides to consult Faunehm to learn more of the great wyrm.
Orn Khai and the Warrior of Light visit Faunehm to learn of Nidhogg's views on mankind and the catalyst for the Dragonsong War. She advises the two to offer mist lilies, flowers that Nidhogg was fond of. They journey to Gyr Abania, the site of Shinryu's defeat and where his eyes were destroyed. The Warrior and Orn Khai arrive at the Royal Menagerie and pay their respects to Nidhogg. Satisfied that Nidhogg's memory was honored, the pair journey back to the Observatorium and share Faunehm's story with Alberic, who plans to impart it to the Temple Knights.
Nidhogg is voiced by Simon Greenall in all versions.
Nidhogg appears as a boss. In the first fight at the Aery, Estinien uses the Eye to hold back the great wyrm's power, and must be protected from Nidhogg's minions. Nidhogg later appears the final boss in the Final Steps of Faith and as an optional Extreme battle in The Minstrel's Ballad: Nidhogg's Rage in patch 3.3.
Níðhöggr (meaning "malice striker" in Old Norse, commonly anglicized as "Nidhogg") is a dragon in Norse mythology who would eat the roots of Yggdrasil, the world tree.The