Gear Fourth is the strongest known form of Monkey D. Luffy that he developed at some point during the two-year time-skip training with Rayleigh on an island called Ruskaina. This form works on the basis of Luffy inflating his muscles and then using the full power of his Haki to coat his arms, legs, and some of his torso.

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Gear Fourth has a total of 3 known forms at the moment, however, it is highly likely that there are going to be more in the future of the One Piece story. Being Luffy's strongest Gear, the attacks offered by it are in a league of their own compared to the others.

10 Double Culverin

Double Culverin Luffy

Double Culverin is one of the strongest techniques used by Luffy in Gear Fourth. It is a much stronger version of the Twin Pistol attack and sees Luffy make use of the contraction offered by his Haki to make his attacks stronger.

When used with Python, it can chase the target as much as possible and eventually lands a powerful blow that can even make the strongest of characters bleed.

9 Jet Culverin

Jet Culverin Luffy

Jet Culverin is an attack used by Monkey D. Luffy in his Gear Fourth: Snakeman form. This technique sees Luffy make use of excessive speed. By retracting his arm and firing it at a high speed, Luffy can hit opponents faster than the eye can see.

Every time the arm changes its direction, it accelerates further, making it even faster and ultimately, impossible to evade in a fight. The force generated is enough to send one of the Sweet Commanders flying away.

8 Rhino Schneider

Rhino Schneider Luffy

Rhino Schneider is utilized by Luffy in mid-air while using the power of elasticity to fly. Coming towards the target at an extremely high speed, Luffy retracts his legs into his body and unleashes powerful kicks.

This technique was used against Donquixote Doflamingo for the very first time and it was powerful enough to send him flying across Dressrosa.

7 Kong Gun

Kong Gun One Piece

Kong Gun is the Gear Fourth version of Gomu Gomu no Bullet and is thus one of the hardest hitting techniques that Luffy has in his arsenal. It is his go-to move in Gear Fourth and the very first technique of this form that he showed off in the story.

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Kong Gun allows Luffy to hit his target with incredible force and cause them a tremendous amount of damage. Its power was great enough to overpower even Charlotte Katakuri, whose Haki was superior to Luffy's at the time. The raw power this technique packs is incredibly high, as seen several times in the story.

6 Leo Bazooka

Leo Bazooka One Piece

The Gear Fourth version of the Gomu Gomu no Bazooka, Leo Bazooka was first used against Donquixote Doflamingo in the Dressrosa arc of One Piece. This technique sees Luffy accelerate towards his target using his elasticity and then hit them with both hands using all his might.

Two of these hits were considered to be enough to deal with Donquixote Doflamingo by Luffy, which just goes to show how powerful it truly is.

5 Black Mamba

Black Mamba Luffy

Black Mamba is one of the techniques of Luffy's Gear Fourth: Snakeman and thus utilizes speed more than power. In his fight against Katakuri, Luffy used this technique to land several blows on his opponent by using a technique similar to Gomu Gomu no Gatling, only much more dangerous.

With each turn, Luffy's fists speed up further, making it impossible to dodge every strike. Despite being able to see the future, Charlotte Katakuri struggled to keep up with the power of this technique.

4 Kong Organ

Kong Organ Luffy

Utilized by Luffy in his Bounce Man form, Kong Organ is a stronger version of Kong Gun and sees both of his fists being used in battle. By moving them side to side at a very high speed, Luffy is able to deliver multiple blows to the target extremely quickly, making it seem as if he's got many fists.

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Kong Organ was first used against Charlotte Cracker and it was powerful enough to destroy his biscuit soldiers with ease.

3 Cannonball

luffy is using tankman stuffed version form in gear 4

Gomu Gomu no Cannonball is a unique attack that Luffy can use in his Gear Fourth: Tankman state. This technique requires the opponent to charge towards Luffy and then get swallowed up by his belly, which keeps on retracting due to Haki and ultimately fires off the opponent with extreme ferocity.

This technique sent Cracker flying from the Seducing Woods back to Whole Cake Chateau and one-shot him in the process. However, it is quite limited as to how Luffy can use it as well.

2 King Cobra

King Cobra Luffy

King Cobra is the strongest technique of Luffy's Gear Fourth: Snakeman and its power were enough to knock out Charlotte Katakuri in battle. To use King Cobra, Luffy fires a Jet Culverin and as it twists and turns to gain more momentum, Luffy inflates his arm further to make it much larger.

Upon delivering the final blow, it's accumulated an incredible amount of momentum and strikes with tremendous power.

1 King Kong Gun

Gear 4 King Kong Gun

King Kong Gun is Luffy's strongest known technique in the series so far. It sees Luffy prepare a Kong Gun and then inflate his arm further to giant sizes, similar to how he does it in Gear Third.

Upon unleashing this massive fist, nothing can stand in Luffy's way. When used against Doflamingo, it was enough to one-shot him and even shattered the plateau of Dressrosa. In Wano, Luffy can now use a stronger version of this technique with Ryou, and it also puts a lot less strain on his body.

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