Magu Magu no Mi

The Magu Magu no Mi is a Logia-type Devil Fruit that allows the user to create, control, and transform into magma at will, turning the user into a Magma Human (Maguma Ningen). It was eaten by Fleet Admiral Sakazuki, formerly known as Admiral Akainu.

Strengths and Weaknesses
The main strength of this Devil Fruit is that it allows the user to produce magma to attack their opponents with. The intense heat can vaporize an iceberg instantly and boil the seawater that the magma lands in. With this power running for a ten day battle, it was strong enough to permanently change the weather of one half of an island into a blazing inferno.

As a Logia, it can let physical attacks, such as punches and slashes, harmlessly pass through the user unless they are imbued with Busoshoku Haki. Other ways the user can be hurt are if they are touching Seastone, being caught off guard (assuming they not trained to transform by reflex), and being attacked by the fruits elemental weakness (though none have been revealed so far). Weapons, such as swords, were also shown to melt after coming into contact with him.

Among all the Devil Fruits, the Magu Magu no Mi has the highest offensive power. The strength of this fruit is powerful enough to take on people like Emporio Ivankov and Jinbe with minimal effort.

This fruit's ability is naturally of a higher order than the fire-manipulating Mera Mera no Mi, with the magma produced able to consume the opposing flames, and neutralize the fire-based intangibility, harming the user.

Aside from the standard Devil Fruit weaknesses, the powers do not seem to be weak against anything specific. In fact, the only things that the Magu Magu no Mi could not burn were the flames produced by Marco's Mythical Zoan fruit (however, in the anime, Sakazuki was still able to push Marco aside in order to reach Luffy with another burst of magma), Vista's swords, Shanks' sword, and Whitebeard's bisento. Additionally, despite having abilities naturally vulnerable to the fruits power, Aokiji was able to deal grievous injuries to the other Admiral during their ten day duel. Like any Devil Fruit, Busoshoku Haki can bypass its intangibility.

So far, non-canon media seems to give the fruit's user a supposed weakness to water. One example is in the game One Piece: Unlimited World Red. If Sakuzuki punches an ice wall, his magma body would be doused in water and hardened, immobilizing him for a short period. While in One Piece: Pirate Warriors (the first game), the boss fight against Sakazuki involves utilizing ice boulders scattered around the arena; this prompts Luffy to pick them up to lob them at Sakazuki, disabling his Logia state for a while and making him vulnerable to standard physical damage.

Other than that, the user is affected by standard Devil Fruit weaknesses.

Usage
Sakazuki's signature method of offense is to transform his fist into magma and expand it with a forward motion, usually in the form of a punch (in the anime, it is also shown that Sakazuki can launch his magma fists, much like a rocket punch). When it comes to transport, Sakazuki can move at extremely high speeds by launching himself like an actual volcano blast towards his target, and can even melt solid earth and rock to make tunnels to move through the underground.

Just by forming an attack, the heat coming off of his body has been shown to melt enemy weapons around him. He has been shown to repeatedly pierce through the bodies of his adversaries with ease using his power, and was responsible for the complete destruction of the Moby Dick.

Along with the incredible corrosion and temperatures, the magma-based attacks also carry highly explosive properties; one attack is enough to cause an explosion capable of inflicting tremendous damage throughout the entire battlefield. In the anime, this Devil Fruit also carries a concussive force as Sakazuki used it to clash with Whitebeard's quake-imbued fist.

Named Techniques

 * Dai Funka (Dai Funka, literally meaning "Big/Great Eruption"): Sakazuki's signature technique. He transforms his fists into pure lava before throwing it forward, like an over-sized rocket (similar to Luffy's Gomu Gomu no Gigant Pistol or Ace's Hiken). The explosion causes volcanic rock to hit the ground, in a method similar to meteors. This was first seen when he used it to evaporate an iceberg hurled at his fellow Marines by Jozu. According to spectators, the battlefield resembled an apocalypse after this one attack.
 * Ryusei Kazan (Ryūsei Kazan, literally meaning "Meteor Volcano"): Resembles Dai Funka, but with multiple magma fists rather than just one. Sakazuki points both fists into the air and fires a great number of magma fists upwards in order to let them rain down upon the battlefield, causing enormous amounts of area damage. It resembles a cross between a volcanic eruption and a meteor shower. This was first used to destroy the ice floor that Aokiji created, along with the pirates who were standing on it. It also boiled the seawater, scalding anyone who remained in it. He managed to take out Whitebeard's flagship, the Moby Dick, with this technique. In the anime, the meteors first fly high into the sky and above the clouds, and then fall back down as if though they truly descended from space. The anime also added a fireworks' sound effect during this attack. In the anime, Sakazuki can also use Ryusei Kazan as a close-range rapid projectile attack, as seen when he fired it off against Whitebeard, and as his Kizuna Rush/Level 2 special in Pirate Warriors 3.
 * Inugami Guren (Inugami Guren, literally meaning "Dog Biting Crimson Lotus"): Sakazuki creates a wave of magma, shaped like a dog's head with fangs, and launches it against his opponent. It was first used against Whitebeard. Notably, Inugami (Inugami, literally meaning "dog god") is the name of a mythological Japanese creature, which resembles a dog. Although it remained unnamed in the manga, the technique's name is introduced in the anime. In the video game Gigant Battle, the technique is called Gansho Kenga (Ganshō Kenga, literally meaning "Magma Dog Fang").
 * Meigo (Meigō, literally meaning "Dark Hound"): Sakazuki transforms his hand into magma and lashes out at the opponent with a claw-thrust. This technique is powerful enough to melt off part of Whitebeard's head with a glancing blow. In the anime, in order to severely censor the gore, this technique's execution and function are different: Sakazuki punches into and pierces his opponent's body with a molten fist in a stance similar to Dai Funka, and then detonates it, filling the victim's body with magma and causing massive internal damage. This caused Whitebeard's stomach to be burned from the inside, while leaving a residual fire flickering at the wound.

Video Game Only Attacks

 * Bakuretsu Kazan (Bakuretsu Kazan, literally meaning "Exploding Volcano"): Sakazuki transforms his hand into magma, and then punches the ground. This results in an eruption of volcanic rocks around the punch area and several spots around it, inflicting damage to anyone within the blast radius. This technique is seen only in One Piece: Pirate Warriors (as Akainu's final basic attack string input, his C2 first input and used as a CPU) and J-Stars Victory VS. (as a special move; the latter game allows the attack to strike at far distances underneath someone, and is more clearly named).
 * Kazan Bakuhatsu (Kazan Bakuhatsu, literally meaning "Volcano Explosion"): A variation of the above used as a CPU-only attack in Pirate Warriors, where he performs his normal attack string finisher to rapidly erupt lava balls from below his target's feet. The move's name can be heard if a mod is used to play as the CPU version of Sakazuki.
 * You're Next!: Sakazuki transforms his body into magma and performs a uppercut with his left fist made of magma, then follows up the attack with a punch with his right fist (when facing a single opponent). If fighting against a team of opponents, the uppercut will force the opponent to swap out and the follow-up attack will hit the teammate that is swapped in. This technique appears in One Piece: Burning Blood as Sakazuki's Unique Special Attack.