Erik

Cobra is a member of the Oración Seis, a dark guild composed of highly powerful mages. He, along with the other Oración Seis, seek to find Nirvana, a destructive magic power that was sealed long ago.

Appearance
Cobra is moderately sized man with red hair, his nose is more snake. He wears a white jacket over a black shirt with red pants, which fit tightly. He is also almost always seen with a large snake coiling around him.

Oración Seis arc
He, along with his group, attack the alliance consisting of Fairy Tail, Blue Pegasus, Lamia Scale, and Cat Shelter and easily decimates them. His target throughout the battle is Erza Scarlet who manage to hold her own against him and the other Oración Seis members until Cobra manages to "hear" her movements and uses his snake to bite her arm, poisoning her, though he mentioned it would not kill her outright just very slowly. He was later sent by Brain to follow Gerard to find Nirvana in which he succeeded. As Cobra continued to watch, Erza showed up. Cobra thinks that there's no way she could have survived and that he must stop her from harming Gerard, but over hears about Gerard's amnesia.

As he confronts Gerard about Nirvana, he learns that Gerard has placed a self destruction spell on it and he tries to undo it. He tries to also regain Gerard as an ally but he becomes horrified as he sees that he placed a self destruction spell on himself. However, Blaine soon appears and easily cancels the self-destruction magic and activates the second stage of Nirvana with a triumphant Cobra. Nirvana then sprouts grows and sprouts legs before stomping over the land. Unbeknownst to them the, Fairy Tail members (along with Gerard), are climbing along the legs trying to stop them. Natsu Dragneel, carried by Happy, manages to make his way to the center of Nirvana and attack Brain. But is met by Cobra who too can fly thanks to his pet snake that can grow wings. A mid-air battle commence leading to Natsu having trouble fighting Cobra since he can see his movement. However, Natsu starts to get serious which Cobra begins to realize.

Despite this, Natsu still can't land a blow on him which Cobra reveal is due to his Listening Magic which, similar to Angel's Gemini stellar spirit, allows him to read Natsu's heart and telegraph his movements. Natsu then decides to just charge in and fight blindly. Cobra manages to dodge the moves at first but they suddenly begin to connect due to Natsu shutting off his mind and fighting on instinct. After taking a few hits, Cobra decides to get serious and reveals his Poison Dragon Slayer form, much to Natsu and Happy's surprise.

Cobra proceed to go on the attack, knocking Natsu and Happy through the air with physical attacks then blasting them with poisonous breath, affecting them with poison and hampering their movements. Natsu still nearly manages to hit him regardless, prompting Cobra to comment on Natsu "old style" way of dragon slaying. Cobra then goes onto reveal he not a true dragon slayer, having implanted dragon lachryma into his body dubbing himself a new generation of dragon slayers. He also comment it impossible for a human to learn real dragon slaying magic since he believes the dragons are all extinct.

Natsu goes on the attack once more after hearing this but is knocked into the air. He then has Happy drop him down on Cobra, opting to blast him with a fire breath. But Cobra of course hears the plan and gets behind Natsu, preparing to finish him. In frustration, Natsu unwittingly lets out a high pitched dragon roar which can be heard all around Nirvana. Cobra's strength soon becomes his weakness as his magic magnifies the roar tenfold in his ears. He plummets to Nirvana trying to block out the sound until he the impact from the fall knocks him unconscious.

Magic and Abilities
Cuberos:The snake he uses name is Cuberos and works in sync with Cobra, making the same expressions as him and attacking at his directive. This sync appears to be telepathic as the snake was able to predict Happy's path of attack without any word from Cobra. When it does attack it is extremely fast and along with that has the ability to fly when it unravels wings otherwise hidden on its body.

Listening Magic: Cobra has the ability to hear a persons very soul, allowing him to tell if they were scared, what they were going to do next, and even their thoughts. His use of this magic is so great that he was still able to counter each of Natsu's moves even when he tried to hide his thoughts. Though this only seems to work when the person's "voice" he is listening to is thinking, or has memories. The magic is also a doubled edged sword as high pitched attacks, such as Natsu's roar, can effect the user greatly.

Poison Dragon Slayer: Cobra is stated to have the power of the Poison Dragon Slayer However its later revealed that he not a true dragon slayer, having implanted dragon Lachryma into his body (similar to Laxus and his thunder dragon slayer magic). However this power allows him to change his fist into a dragons claw surrounded by a dark poison aura, it was capable of stopping Natsu's attacks and burning him with poison. He can also eat poisonous mist as supplied by his snake Cuberos for more devastating attacks
 * Poison Dragon Roar: After eating poisonous mist, Cobra lets out a poisonous breath that, when hit, injects virus into his victim's body. Affecting their movement and slowly killing them.
 * Poison Dragon Twin Fang: Cobra hits his opponent with a cross style attack with his claws, poisoning his victim further.

Trivia

 * Cobra is the fifth known Dragon Slayer, and can eat poison to replenish his strength.
 * Cobra is the second known "new generation" of dragon slayer who have there powers due to dragon lachryma in there bodys like Laxus dreyar