Fairy Tail offers a wide variety of complex characters with tragic backstories. Perhaps the most complex character of them all is the main antagonist, Zeref. Though Zeref's existence starts as one big mystery, his truth slowly unravels as the story progresses towards its final arc.

With unexpected relations to multiple characters and hidden secrets behind his evil, Zeref is understandably painted as a dark and mysterious force that is full of surprises. But underneath it all, there are also deep layers of tragedy and sin in Zeref's character that make you simultaneously love and hate him. Here are ten lesser-known facts about this intriguing wizard.

10 He was an Emperor

As someone who lived for hundreds of years, Zeref had a lot of time on his hands. He had so much time that he decided to build an entire empire, the Alvarez Empire, and become its first emperor.

In an attempt to secure enough power to defeat Acnologia, the Alvarez Empire went to war with Fairy Tail. With help from the powerful mages of Spriggan 12, Zeref and the Alvarez Empire put up a tough fight against Fairy Tail and their allies. Despite their eventual defeat, it's worth noting how loyal the Alvarez Army was in fighting for their Emperor.

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9 He was a Genius

Revealed in a series of flashbacks, Zeref was once a normal child with a happy family. After a tragic incident took the lives of his parents and little brother, he began studying at a magic school and allocated all his time and energy into finding a way to resurrect the dead.

In doing so, Zeref discovered extremely complex black magic. This black magic eventually led to the creation of vicious demons in the form of magic books. Though most of the demons served Zeref by doing his dirty work, they were actually created with the intention of killing Zeref himself. But even demons were not enough to defeat him.

8 He was Cursed

Just as Zeref discovered black magic, he was also inflicted with the Curse of Contraction. This curse made Zeref immortal and could kill everything around him if he felt enough love. Because of this, Zeref has unintentionally taken many innocent lives. And to make things even worse, he was forced to live with those sins for hundreds of years.

In fear of the curse's deadly effect, Zeref isolated himself along with his emotions. If he could suppress any sort of feeling of love, no one would have to die to his curse. At the same time, this caused Zeref to become conflicted between good and evil. The lack of love in his immortal life consequently turned his heart very dark.

7 Fairy Tail was Founded Because of Him

History shows that Fairy Tail was first founded by Yuri, Precht, Warrod, and the first guild master, Mavis Vermillion. However, it was Zeref who actually taught each of these wizards how to use magic.

During a time of tension with the Blue Skull guild, Mavis and her allies had no magic abilities to fight back against the dark mages. This changed when Mavis met Zeref and urged him to teach them magic. Thanks to Zeref, Mavis led her side of the war to victory and later founded a magic guild of her own, Fairy Tail.

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6 He was a Father

Zeref created many unique demons from Deliora to Tartaros to E.N.D. But what no one knows is that Zeref also gave life to a human son named August. The only thing that's more shocking is the fact that August's mother was Mavis.

When Mavis fell into a state between living and dead from Zeref's curse, Fairy Tail's second guild master discovered that Mavis had been pregnant with a child. After being abandoned, the child met Zeref who took him in and gave him the name August. While August knew Zeref was his real father, Zeref was unaware he even had a child. In the end, August died without ever receiving parental love from Zeref.

5 He Feared Acnologia

Acnologia from Fairy Tail

Though Zeref was an immortal with incredibly powerful magic, he had one fear: Acnologia. Acnologia was a Dragon Slayer like Natsu, except he also had the ability to transform into a dragon. As a mighty being who seemed to have no remorse in killing, Acnologia was a common enemy that everyone could agree on.

In the war between Alvarez and Fairy Tail, Zeref stated that his goal was to gain enough power to defeat Acnologia. He believed he would be the only one strong enough to stop the dragon, so he took that duty upon himself. It turned out, however, that the reason why Zeref wanted Acnologia gone was that he was afraid of being tortured by him for the rest of his eternal life.

4 He Didn't Want to be Immortal

Many villains are driven by greed and power. Often, they seek something as inhuman as immortality. But once they obtain immortality, they may realize it's not as wonderful of a life as one would assume. Zeref found this out the hard way.

Although Zeref never intentionally sought out immortality for himself, he desperately searched for a way to bring his little brother back to life. Through trying to defy the circle of life, Zeref was cursed with immortality as part of the Curse of Contradiction. After killing and hurting so many people with his curse, Zeref wished he could die to atone for his sins--but it just wasn't possible.

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3 He had a Close Relationship with Mavis

Though they seem to be enemies at opposite sides of a war, Zeref and Mavis shared many things: a past, a curse, a kiss, and a child.

When Zeref first met Mavis, he taught her how to use magic, including the dangerous black magic called "Law". As a consequence of using an underdeveloped version of Law to save her friends, Mavis was inflicted with the same curse as Zeref. The two struggled to cope with the deadly sins of their curse but found comfort in each other. As a result, they shared a kiss, conceived a child, and accidentally drained Mavis's life with the curse.

2 He was Natsu's Brother

Initially, not much was known about Natsu's past or why he was raised by a dragon. It wasn't until Zeref shared more of his own backstory that Natsu was revealed to be his little brother.

Struck with grief over the loss of his little brother, Zeref preserved Natsu's body as he tried to find a way to revive him. He eventually was able to achieve this goal and resurrected Natsu as a demon called E.N.D. It's unfortunate that Zeref's love for his brother was what contributed to his dark and destructive future.

1 He was Killed with Love

Even though Zeref was cursed with immortality, a part of him always wished that he could somehow still die. He even went as far as making a demon out of his little brother, hoping Natsu would be stronger than the curse itself.

In their final battle, Zeref obtained Mavis's magic and a huge surge of power, but Natsu was still able to immobilize him. Rather than continuing to beat up his older brother, Natsu left it to Mavis to end things with Zeref. After Mavis confessed that she loved Zeref, the Curse of Contradiction was finally broken with the power of love, and the two were able to die together in peace.

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