Zeref is considered to be the strongest and most evil mage in all history, who possesses a mysterious, powerful and very dangerous magic, known to create dreadful demons and incredible monsters of mass destruction. Despite his evil doings, he appears as a self-hating and reclusive young man who cannot control his powers willingly.
Zeref was said to have been the darkest, most evil Mage in the history of the Magic World. He lived up to his reputation by being the only one to master the Black Arts of Magic and the creation of monstrous demons, which continue to wreak havoc.
Zeref had isolated himself and seems to have a gentler, melancholic personality. He is usually seen behaving very calmly and peaceful in extreme situations. Apparently, he wishes for death to be his punishment in order to atone for all the sins he has committed and is worried that he may commit much more in the future, and when he comes to realize that Natsu is nowhere near ready to kill him just yet, being too weak to take Zeref on, he breaks down in tears and he enrages unwillingly. He commits incidents out of his control, however, he is still shown to be extremely intimidating when he is angry, and will not hesitate to bring judgement upon those he believes to be evil, such as Grimoire Heart, the powerful enemies of Fairy Tail during the Tenrou Island Arc.
Long ago in history, stated to be around 400 or so years ago, Zeref had witnessed many people dying in war and losing their lives. He became cursed as a result and helplessly started to take the souls and lives of both the innocent and the guilty, without his own intention.
Because of Zeref’s unstoppable actions, he was sealed away for many centuries. However, one day he apparently managed to escape and set himself free, despite the fact that Grimoire Heart, whose goal was to collect all the keys to Zeref’s prison and free him, did not collect all the keys to his prison. Fortunately, the darkness inside of Zeref still remains sealed. The slumber somehow made him a very kind person as he cares for others’ safety now and wants to be judged with death, once and for all. He also apparently learned about Natsu, realizing that he may be the only one capable of killing him someday.
Mavis Vermilion, the “Fairy Tactician”, was the first Guild Master and the founder of Fairy Tail. Mavis is a kind and protective guardian of Fairy Tail, despite the fact she has been dead for several years now. Mavis is also very widely known as the creator of the powerful and fearsome magic known as the “Fairy Glitter” and the “Fairy Sphere”, two immensely powerful spells, used solely for the good of the guild.
Although one may believe that the first master of Fairy Tail was a powerful, mighty and serious mage, Mavis is in fact the opposite. She is very playful and to a certain degree, somewhat childish in her own lovable ways. She even left her burial grounds, Tenrou Island, only to spectate cheer on her beloved Fairy Tail in the Grand Magic Games. Although she can’t do much in her current and temporary physical body, she assists the guild greatly by offering her instinctive and tactical skills, which helps lead Fairy Tail in the right direction, and on route to success!
Zeref’s magic can easily be compared as the opposite to Mavis’ magic. Zeref’s magic can be seen as the epitome of evil and chaos, being that his magic is based upon Black Arts and mysterious magic, bringing countless demons to life. He also causes any living things in the surroundings to die when he uses magic. However, Mavis’ magic can be seen as the opposite, the epitome of peace and light, being that her magic is based upon the radiance of merciless light that rejects the presence of any foes. It is also an exceedingly complex and unfathomably intricate spell that collects and concentrates the light of the sun, the moon and the stars. Zeref can be seen as the Antithesis of Mavis Vermillion, and the other way around. Both mages wield a magic of which exceeds what would be termed as “normal”.