Igneel

Igneel (イグニール Igunīru) was a Dragon known as The Fire Dragon and The Flame Dragon King, and is the foster father of Natsu Dragneel.

Appearance
Igneel is a gigantic Dragon whose bodily majority is covered with dark, red scales. Igneel's lower body, specifically his belly, the inner portions of his long tail, and legs, is beige in color. Igneel also has noticeable scars on his belly and neck, with the largest one, which is X-shaped, located around the center of his body. His back has numerous black spikes, reaching down from the back to the end of his tail. Igneel has a triangular head with horns, a pair of large, round eyes with yellow sclera (which are usually seen as glowing, obscuring his dark, round pupils) and a sharp horn pointing upwards just above his nose. Igneel also sports very sharp canine teeth, and has claws with long, sharp, red nails. Igneel's large bony wings resemble a bat's, with rippled tips. Additionally, Igneel has four hind legs.

Personality
Igneel has been shown to be a loving father figure towards Natsu, before his untimely departure. Despite leaving Natsu, Igneel, however, is shown to be incredibly protective of Natsu, and watches him from afar. Contrary to his quite often portrayed loving personality, Igneel can also be rash, angry and violent when he feels the situation calls for it. He has also shown a high degree of arrogance, referring to himself as "the one and only Igneel" during Grandeeney's visit. It is also implied by Igneel himself that before he met Natsu he did not like humans in the slightest, but his encounter with the boy and raising of him gave him the ability to love them.

According to Grandeeney, like Natsu, Igneel has a tendency to take things to the excess.

History
Igneel, also known as the Flame Dragon King, dueled with his close friend Atlas Flame several times, usually arising atop and consuming the flame clad Dragon's flames. Four hundred years ago, Igneel, out of choice, failed to destroy the most vile Demon in the Books of Zeref: E.N.D. Many years later, Igneel taught a young human boy, Natsu Dragneel, how to write, speak and use his signature Lost Dragon Slayer Magic: Fire Dragon Slayer Magic, which gave Natsu the traits of Igneel himself. However, in an attempt to watch over Natsu and stop him from turning into a Dragon like Acnologia, Igneel, alongside the foster parents of the other Dragon Slayers, entered the bodies of their foster children via a secret art so as to create antibodies to prevent them from doing so. Igneel, additionally, had a second motive: to wait until he could kill Acnologia. All of this occurred on July 7th, X777; Igneel left Natsu to fend for himself with so much as a goodbye or an explanation for his reasons for doing so.

Tower of Heaven arc
Note: Events take place in the Tower of Heaven arc in the manga, but Fighting Festival arc in the anime. After the events that transpired at the Tower of Heaven, Igneel is seen residing in a volcanic region, talking to the Dragon who raised Wendy Marvell, Grandeeney, about Natsu. Igneel immediately orders Grandeeney to leave, while she warns him that if Natsu continues fighting as recklessly as he has, he may wind up dead. Igneel then makes a reference to the Black Wizard, Zeref, and the Dragons' removal from human affairs. He then shows that he is in fact very firm about leaving humans alone, especially Natsu. Hearing these words, Grandeeney leaves, hoping that Natsu's friendship with Wendy will be better than his "friendship" with Metalicana's foster son, Gajeel Redfox.

Oración Seis arc
Note: This event only occurs in the anime and does not constitute as canon material. During Natsu's fight against Zero, Natsu is sent to the Land of Nil through Zero's Magic Genesis Zero, and opening the Gate of Wraithwail. Through there, Natsu is about to lose hope, cursing everything he had done. Suddenly, he hears Igneel's voice, saying that Natsu should not be defeated by the likes of Zero. Igneel also mentions that this is what a child of Igneel is and a flashback focuses on Natsu questioning Igneel on how he's supposed to destroy a mountainous rock. Igneel explains to him that he must not let his feelings get the better of him, saying he must not lose faith in his power. He encourages Natsu, saying he's a Dragon Slayer and that he must not forget the pride that comes with that title. Igneel concludes by stating that he is with Natsu, and, with this, Natsu manages to burn off Zero's Magic and come back from the Land of Nil.

Grand Magic Games arc
Igneel is seen talking to himself about the potential of the Dragon Slayers Weisslogia and Skiadrum created. He then wonders if humans will ever surpass Dragons, or if it is merely a dream. Igneel then notes that the time for the Dragons to take action has come, as the Dragon King Festival draws ever near.

Tartarus arc
While Acnologia springs into action, arriving at the Tartarus' location, Igneel wonders if "the time has come". Talking to Natsu whose body reacts to Acnologia, Igneel expresses his belief that Natsu is capable of E.N.D.'s defeat. While Natsu is confused, not knowing why he can hear the Fire Dragon, Igneel comes out of the mage's body and states that he has to deal with Acnologia. Revealing that he has been inside Natsu's body this whole time, Igneel asks for forgiveness and tells his son to live as he charges the Black Dragon.

Igneel clashes with Acnologia in mid-air and the two begin to fight over the Tartarus ruins, but are interrupted when Natsu launches himself at Igneel, demanding that the Dragon explain why he disappeared so many years ago. Angered, Igneel tells Natsu to stay away, and uses a large attack on Acnologia to blast the other Dragon back, almost accidentally shaking Natsu off in the process. Grabbing the Dragon Slayer in his claws, Igneel tells Natsu to leave as Acnologia regains his composure after the attack, and, recalling that Natsu works in a guild, asks the Mage to complete a job for him. Igneel then points out Mard Geer in the ruins below, and tells Natsu to go retrieve the book of E.N.D. that he holds. Natsu questions why such a thing is important, though Igneel merely remarks that the book should not be in Mard's hands, and warns Natsu to never open it; he also agrees that the reward for Natsu's completion of the job request will be an explanation of anything and everything Natsu wishes to know. With Natsu agreeing to take on the job, Igneel tosses the Dragon Slayer down to Mard, before he turns to continue his fight against Acnologia. As the battle rages on, Igneel is seen striking Acnologia with his claws set aflame (Iron Fist), while at the same time, his son hits his opponent with a similar technique, Fire Dragon's Iron Fist but fails to injure the Black Dragon.

Soon after, upon witnessing Natsu be overwhelmed by Mard Geer, Igneel calls out to his son, but is nearly struck by Acnologia's Dragon's Roar, which he aptly dodges. Hearing Acnologia claim that he is going to slay Igneel, the latter remarks upon the former's act of speaking with sarcastic wit and they continue clashing midair. Igneel then continues ascending and Acnologia follows him, claiming that he will not escape. As they reach high enough, Igneel states that he is not trying to escape, choosing this height so they can fight to their fullest. However, Acnologia replies that he will destroy his opponent. roughly twenty minutes later, as Face activates, Igneel sends a badly wounded Acnologia plummeting to the ground and stands upon his immobile body, telling humanity not to give in. He then tells everyone that the other Dragons have arrived and, as they all destroy Face, that they are dancing unto the old continent of Ishgar.

Sensing that the other Dragons have finished their deeds, Igneel states that they've won: they've stopped E.N.D.'s revival. Sting then brings up Weisslogia, which Igneel overhears, and tells them that Skiadrum, Metalicana and Grandeeney were all alive inside the Dragon Slayers through a secret art that they performed, and that they had two reasons for doing so, one of which was to prevent other Dragon Slayers from ending up like Acnologia. Before he can let out the second reason, Acnologia rises to continue his fight with Igneel; Igneel screams for Natsu to get E.N.D.'s book before flying off again to deal with his draconian foe. In the sky, Acnologia questions Igneel's motive for staying hidden, but Igneel merely tells Acnologia to leave the humans alone as E.N.D. is not going to be revived, however Acnologia takes insult to this and replies that he fears nothing, to which Igneel replies that he won't let the other Dragon Slayers become like him and readies to clash again.

Igneel, however, is quickly overwhelmed by Acnologia, who derides the Flame Dragon King for being weak despite being their ruler; Igneel replies that he's merely been asleep for awhile, but he is repeatedly body-pressed by the great Black Dragon. As he is continuously beaten, Igneel telepathically contacts Natsu and reminds him that the Dragons hid inside the Slayers to create antibodies to prevent their "Dragonification" and disclosed the second reason: he was waiting until the time was right for him to kill Acnologia. He then tells a worried Natsu not to come to his location and explains that Acnologia was stronger than he anticipated. Hearing that Natsu does not care and that they could fight together, Igneel smiles and bats the Dragon off of him before flying upward and ripping the Dragon's arm off. However, Igneel's body is then immediately ripped in half by Acnologia and as he falls, he tells Natsu that he watched him grow from a child and that the days they spent together were his happiest, as well as that Natsu gave him the ability to love human beings. Igneel is then hit by Acnologia's Dragon's Roar and perishes in the blast.

Magic & Abilities
Telepathy (念話, テレパシー, Terepashī): Igneel is able to make use of this form of Magic, allowing him to communicate with Natsu telepathically.

Dragon's Roar: Similar to other Dragons and Dragon Slayers, Igneel has shown the ability to use his element in the form of an attack coming from his mouth. In Igneel's case, the attack takes form of a large-scale destructive fire breath attack, similar to Natsu's Fire Dragon's Roar and Atlas Flame's, capable of completely destroying the surrounding area in a massive explosion.

Flight: Being a Dragon, Igneel possesses the ability to fly through the air using his wings.

Iron Fist: Igneel hits the enemy with his blazing, hard fist which is powerful enough to blow even the Dragon King, Acnologia away.

Fairy Tail Portable Guild 2
Igneel appears as one of the two major bosses of the PSP game Fairy Tail Portable Guild 2, being the strongest of the bosses.

Fairy Tail: Zeref's Awakening
Igneel makes a second appearance in the sequel, Fairy Tail: Zeref's Awakening, as the strongest boss of the game.

Quotes

 * (To Grandeeney) "Leave this place! Do not interfere with the humans!!!"
 * (To Grandeeney) "Do you mean to anger the one and only Igneel?!"
 * (To Natsu Dragneel) "I, Igneel, am with you!"
 * (To himself about the Dragon Slayers) "Can humans exceed Dragons or is it just an empty dream..."