All Gears Monkey D Luffy In Anime One Piece.
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| Gear Second Monkey D Luffy |
Gear Second (ギア･セカンド Gia Sekando) is where Luffy uses his legs to pump blood throughout his body at a much faster rate. Activating Gear Second also uses a lot of stored energy from his body. Leaving his body exhausted, his heart rate also increases to levels that are normally impossible. His veins are able to withstand this, thanks to the Gomu Gomu no Mi. In this form, Luffy gains a considerable boost in speed and strength.
During the Enies Lobby Arc, Rob Lucci mentions that this ability is similar to steroids because his muscles are receiving enough blood to do things otherwise impossible. Rob Lucci also noted that Gear Second does damage to Luffy's own body and in turn drastically reduces his stamina and his lifespan begins to diminish.
Luffy first discovers this Gear unofficially in the 7th One Piece Movie, where he has a large mechanical arm falling on him, he catches it, and the impact exerts extreme force on Luffy's legs, causing him to unintentionally pump blood at an accelerated rate to perform Gear Second and use the Gomu Gomu no Jet Bazooka (though he simply refers to is as a normal Gomu Gomu no Bazooka) to defeat a giant robotic battlesuit.
After the timeskip, it appears that Luffy has gained enough control over his Gear Second form, that he is able to use it in a single part of his body rather than the whole thing. This in conjunction with his Busoshoku Haki was able to take out a Pacifista with a single punch, something that took the entire Straw Hat crew to do before the timeskip. It seems that Luffy has become more adept with this gear as he has been using Gear Second attacks more frequently than before the timeskip.
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| Gear Third Monkey D Luffy |
Gear Third (ギア･サード Gia Sādo) is where Luffy pumps air through his bones to make them literally gigantic. Obviously, only Luffy can do such a thing by using the Gomu Gomu no Mi. Used with his already-strong physiology, this apparently gives his arm more mass and a larger area to attack with far greater force, but he sacrifices mobility for this strength, as his limbs are now so large that Luffy has extreme trouble moving unless he is in his Fusen form. Another after effect of this is that Luffy is reduced to child-sized proportions, the duration of which is equal to the time he spent in Gear Third. Also, he is able to use both gears at the same time which he uses to defeat Gekko Moriah. The Gear Third technique is first hinted at during Luffy's fight with Blueno, and first used, but not shown when Luffy is chasing Rob Lucci and Spandam, but is not seen until a later battle with Rob Lucci.
After the timeskip, Luffy's Gear Third is vastly improved upon. Previously, Gear Third would increase the size of the majority of Luffy's arm, thus reducing the speed of the attack in exchange for a powerful impact. However post-timeskip Luffy can seemingly control where the air is allowed to "sit" within his limbs, where his fist becomes large but allows a large mass to form behind the fist as the equivalent of the mass he would have achieved having his arm fully inflated. This allows a majority of Luffy's arm to remain as it is, allowing him to stretch it, thus allowing him to attack much faster than before the two-year absence.
Luffy is also shown using Gear Third at the same time as Busoshoku Haki causing his arm to turn black and harden, with his arm in the ocean (which would normally drain a Devil Fruit user of their power). While he is affected by the ocean, he still lands a punch which knocks the Kraken out. Luffy is confirmed to have overcome his weakness of shrinking when deactivating this Gear, after inflating both his arms and using "Gomu Gomu no Elephant Gatling" on Noah for a prolonged period of time and not turning into his chibi form.
