In the world of One Piece, anyone who eats a Devil Fruit is granted unique powers that they later hone to perfection and use to suit their needs, whether it's for defense, offense or any other use. There are three types of Devil Fruits, among which Logia is believed to be the strongest type. In fact, Mera Mera no Mi is one the strongest Devil Fruits in the entirety of One Piece. This Devil Fruit has the ability to transform the user's body into flames, making them invulnerable to all physical attacks except those imbued with Haki.

It is also one of the few known Devil Fruits to have more than one user. It contributes significantly to Ace being one of the most feared pirates in the world. Because this Devil Fruit is so incredibly strong, Ace rarely had to rely on his Haki. After his tragic death, his sworn brother Sabo takes the powers of Mera Mera no Mi himself, further inheriting his will as well.

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The Strengths and Weaknesses of One Piece's Mera Mera no Mi

Portgas D Ace using his Mera Mera no Mi Devil Fruit in One Piece.

Also known as the "Flame-Flame Fruit," this Devil Fruit allows the user to create, control and transform into fire at will. The fruit has a round, orange-colored appearance, with many flame-shaped components having swirl patterns. Even the stem on the top of the Devil Fruit is swirled. So far, all the Logia users are known to be Luffy's adversaries in one way or another except in the case of the Mera Mera no Mi, as the only two known users are his brothers. Just like any Logia type, Mera Mera no Mi allows the user to produce as well as become fire, allowing them to create devastating fire-based attacks.

While the users are able to create fire-based attacks, they also gain high resistance toward most heat-based attacks. The user can use these flames to boost their physical attacks. However, the resistance is not full-proof against powerful opponents such as Akainu, who has the power of Magu Magu no Mi. Another weakness is that when this power clashes against certain Logia users, it can come to a stalemate. The power of Mera Mera no Mi isn't enough to overwhelm smoke or ice Logia users; instead, these powers cancel each other out. Apart from these few drawbacks, Mera Mera no Mi users also suffer from weaknesses to seawater and sea prism stone, just like any other Devil Fruit user in One Piece.

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Ace's Mera Mera no Mi Techniques

Ace using Devil Fruit powers in One Piece.

Despite being proficient in all types of Haki, Ace relies mostly on his Devil Fruit powers in combat. One of his popular techniques called Kagero, meaning Heat Haze, allows him to shoot fire from his palms, as shown in his fight against Smoker in the "Arabasta" saga. Enjomo, which translates to Blaze Net, is a defensive technique where Ace creates a circle of fire around any designated area to prevent others from entering or leaving. He can use this technique to trap an enemy within it as well as protect himself by blocking them from entering the circle. Hiken, meaning Fire Fist, is Ace's signature attack, earning him the nickname Fire Fist Ace.

This technique allows Ace to turn his fist into flames, launching strong punches powerful enough to plow through multiple ships in one blow. One of his most powerful techniques, Enkai -- literally meaning Flame Commandment -- allows him to gather a massive amount of flames around his body to prepare for another iconic technique called Hibashira, or Fire Pillar. Following Enkai, Ace can shoot the collected flames upward, destroying the opponents above him. He can also launch this attack downward when he's in midair.

Ace's ultimate technique is Dai Enkai: Entei, meaning Great Flame Commandment. This allows him to create a massive spiraling fire centered on his location and gather it at his palm. Ace then turns the gathered fire into a gigantic fireball, creating a small sun and hurling it at his opponents to completely annihilate them. The only time Ace uses this attack is against Blackbeard, the battle that leads to the former's downfall. Moreover, Ace also uses a technique called Hiyaku, meaning Fire Leg, to cover his feet in flames, giving him a boost as he pushes himself into the air and comes downward to launch a devastating attack on his opponents.

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Sabo's Mera Mera no Mi Techniques

Sabo Using The Flare-Flare Fruit

Despite having the same Devil Fruit, Sabo uses the powers of Mera Mera no Mi in a very distinct way. As the second in command of the Revolutionary Army even before gaining the power of a Devil Fruit, Sabo has proven his might as a fighter. Because he already has an accomplished fighting style, Sabo primarily uses the power of his Devil Fruit to incorporate into his already-existing attacks such as his iconic Dragon Claw. What's remarkable is that just seconds after consuming the Devil Fruit, Sabo is able to utilize its powers effectively.

Although he struggles a bit to control his new powers, it doesn't take long for him to get used to them, and he even faces powerful fighters such as Admiral Fujitora and Jesus Burgess. Since Sabo is shown to inherit Ace's will, it's only fair that he also inherits the latter's signature technique, Fire Fist. Sabo can also turn his fist into flames, launching an attack powerful enough to completely shatter a thick stage made up of stone. Furthermore, Sabo uses this attack in the Corrida Colosseum, mere moments after consuming the fruit.

Additionally, Sabo creates his unique attack called Moeru Ryusoken: Kaen Ryuo, literally meaning Burning Dragon Claw Fist: Fire Flame Dragon King. With this technique, Sabo fully incorporates the powers of Mera Mera no Mi into his own fighting style. Sabo forms his "talons," coats them with Armament Haki, ignites them, slams them into his opponent, spins them around and then blasts his target away with a burst of fire. He first used this technique against Burgess, who was sent flying a huge distance while suffering from flame burns.