Most Logia-type Devil Fruits in Eiichiro Oda's One Piece confer powers that are a cut above the other two categories in their basest form. On ingesting these fruits the user receives a broad range of abilities covering long range attacks, environmental manipulation, and most importantly, the power of intangibility. At the start of the series, this proved to be a major problem for Luffy and the Straw Hats, where they had to devise specific countermeasures against the fruit in each case. It was only the introduction of Haki that evened the playing field between Logia users and the general populace, and still leaves a considerable gap in power that would remain difficult to address. Needless to say, several of the most powerful combatants in One Piece are Logia users, as seen in the case of Blackbeard, Fleet Admiral Akainu, Admiral Kizaru, Smoker, Crocodile, Enel, and many others.
One of the most iconic and sought after fruits in this class however, is the Mera Mera no Mi, which was most recently eaten by Sabo, Chief of Staff of the Revolutionary Army and Luffy's sworn brother. Prior to the events of the Dressrosa Arc, where Sabo came to possess the fruit, it was made famous by the son of the Pirate King, Portgas D. Ace, who was also Luffy's sworn brother and the 2nd Division Commander of the Whitebeard Pirates until his demise during the Summit War of Marineford. Ace's exploits with the fruit earned him the epithet of "Fire Fist," which was also his signature attack when using the power of the Mera Mera no Mi. Renowned for his explosive power, flashy fighting style, and innovative use of the fruit's fiery capabilities, Ace's time with the fruit made it an emblematic part of One Piece, and one of the most coveted Devil Fruits in the story.
A Roaring Inferno
Named for the Japanese onomatopoeia that refers to something bursting into flames, the Mera Mera no Mi was eaten by Ace after his departure from Dawn Island, where he was shipwrecked on an island with the alias of Masked Deuce. After unsuccessfully trying to escape, Ace was prepared to eat a fruit to abate his starvation, which unbeknownst to him was the Mera Mera no Mi. He decided to split the fruit but ate it first and managed to gain its power. The pair would then escape and go on to form the Spade Pirates. A round orange fruit with whirling flame-like patterns across its surface the Mera Mera no Mi bears a fitting resemblance to the Devil Fruit powers it grants, capped by a swirled stem. Like most other Logia types, the fruit's greatest benefit is the intangibility it grants, alongside allowing its users to create, manipulate, or turn their bodies into fire.
This opens up the door for extremely powerful fire-based attacks, offering greater resistance to heat, or the option of augmenting physical attacks with fire, while also allowing a user to ignite their own bodies and burn opponents if they get too close. When pitted against other Logia types, the fruit seems to hold its own quite well and achieve a stalemate, as seen in Ace's fights against Smoker and Aokiji. Unfortunately, the one fruit it seems to be inferior to is Akainu's Magu Magu no Mi as it falls below it in the elemental hierarchy, where magma is considered to be even hotter than fire. Even the intangibility provided by the fruit is rendered null and void as Ace was unable to defend against any of Akainu's attacks which led to his defeat and eventual death at the hands of the future Fleet Admiral.
The Most Sought After Logia
The aftermath of Ace's death saw his name and fame grow ever greater, and with it, the profile of his Devil Fruit. When Luffy and the Straw Hats landed in Dressrosa's Corrida Colosseum, they were astounded to find that the Mera Mera no Mi was now in the hands of Donquixote Doflamingo who had offered it as a prize for the winner of a tournament being held at the venue. Enraged by this knowledge, Luffy vowed to enter the tournament and win it, even though he would not have been able to eat the fruit and take its power for himself. Luckily for him, another one of his sworn brothers, Sabo, who was presumed dead, had also made his way to Dressrosa along with his comrades in the Revolutionary Army. Sabo eventually went on to win the tournament after impersonating Luffy in the final clash, becoming the Mera Mera no Mi's next user, and inheriting Ace's will.
In the time since the Summit War, the Mera Mera no Mi had come to be known as the Devil Fruit wielded by the son of the former Pirate King. With its destructive capabilities having been put on full show for the world to see at Marineford, its fame as the Fire Fist's Devil Fruit grew even greater, to a point where every contender at the Corrida Colosseum was willing to risk life and limb in order to gain its powers. Doflamingo intended to use it as a means to erode the foundation of Luffy's alliance with Trafalgar Law, where he knew that the Straw Hat captain would charge in with no second thought in order to prevent Ace's Devil Fruit from falling into the wrong hands. To Luffy's good fortune, Sabo was able to win the fruit in his stead, preventing his worst nightmare from coming true.
Two Generations Of Fire Fists
Ace generally named most of his Mera Mera no Mi-enhanced attacks after Japanese phrases that led back to certain specific mythologies. Perhaps the most iconic of them all would be "Hiken" which literally translates to "Fire Fist," and features him turning his fist into flames and launching a powerful column of fire towards his opponent. It is said that Ace had sunk countless battleships and defeated hordes of extremely strong pirates with his flame powers, and this attack in particular. On consuming the fruit after winning the Corrida Colosseum tournament, Sabo unleashed his own version of Hiken, to signify that he was prepared to take on the role Ace had once played in Luffy's life. Ace's offensive arsenal also included a number of short and long range attacks, where he would net-like create constructs from fire with "Enjomo," or amass flames and shoot a gigantic pillar of fire at his opponent with "Enkai" and Hibashira."
Other attacks include "Hotarubi," where he shoots countless small fireballs that resemble fireflies, "Shinka: Shiranui," where he hurls lances of fire, or "Jujika," which takes form as a cross-shaped column of fire formed by the intersection of his index fingers. Many of them were on display between the fight between Ace and Blackbeard, which also showed off his most devastating attack, illuminating the full extent of the Mera Mera no Mi's astonishing power. Named "Dai Enkai: Entei," this attack sees Ace gathering flames and concentrating them at a point in his palm which then expands into a gigantic fireball reminiscent of the sun. He then hurls the attack at his enemy to wipe them out completely. Aside from these attacks, Sabo has also demonstrated his own take on the Mera Mera no Mi's abilities, merging them with his Ryusoken (Dragon Claw Fist) fighting style in "Moeru Ryusoken: Kaen Ryuo," which also makes use of Armament Haki. In this manner, the late Fire Fist Ace, and his successor, now dubbed the "Flame Emperor Sabo," have shown the potent power of the Mera Mera no Mi, leaving no doubt as to why it is desired by so many.