Since the start of Black Clover, the manga has explained how people with the four-leaf grimoire are the ones who are loved by mana. With such a description, one may be led to believe that the most skilled magic user should be someone who has the said four-leaf grimoire. Surprisingly, the most skilled magic user is a three-leaf grimoire, Magic Knight.
Fans have known Mereoleoan Vermillion as a strong Magic Knight, who tends to do the unfathomable. However, Black Clover chapter 371 saw her pull off a feat that has never been seen done before. This was also evident from Paladin Moris Libardirt's reaction near the end of their fight.
Disclaimer: This article contains spoilers from the Black Clover manga.
Black Clover chapter 371 sees Mereoleona become the most skilled magic user
As seen in Black Clover chapter 371, Mereoleona Vermillion had been exceptionally strong since she was a teenager itself. She was so strong that nobody could keep up with her. Hence, she was forced to train alone by putting herself through harsh natural environments of strong mana regions and fighting inhuman monsters.
Such environments helped Mereoleona to become strong and learn new techniques like mana skin and mana zone. Surprisingly, she was the one who taught the technique to Black Bulls Captain Yami Sukehiro.
In time, Mereoleona became so strong that she believed that she was going to reach the peak. Unfortunately, there was only so much she could achieve all by herself.
Despite that belief, Mereoleona again surpassed her limits in Black Clover chapter 371. After prolonged usage of Hellfire Incarnate, Mereoleona attained her new spell Ultimate Flame Magic: Excelicitus Leonum. This spell allowed Mereoleona to go even beyond Hellfire Incarnate and transcend her human body into mana.
Additionally, the magic spell allowed Mereoleona to resurrect the spirits of her deceased allies. While this factor of the spell is yet to be entirely explained, it is something only Lucius Zogratis has done before single-handedly by turning the dead into Paladins.
However, even in his case, he managed to undergo the ordeal after taking over the mana attributes of his three siblings. Hence, Mereoleona pulling off the feat all by herself was amazing.
As for Mereoleona's transcendence into mana, the feat was something no Magic Knight had ever done before. The one time it was deemed possible in the series, it was done through her. As evident from her three-leaf grimoire, she isn't the most talented or blessed when it comes to mana. However, her skill at handling the same is second to none.
The only other Magic Knight who could possibly do the same in the series might be Lucius Zogratis. However, the manga has yet to showcase any such developments that hint at the same possibility. Therefore, it would be right to say that Mereoleona Vermillion has cemented her place as the most skilled magic user in the Black Clover series.
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