| Arc | Opponent | Gear 4 Form Used | Trigger for Usage | | :--- | :--- | :--- | :--- | | | Donquixote Doflamingo | Boundman | Doflamingo’s Awakened String powers were cutting through Gear 2/3. Luffy needed raw, overwhelming blunt force to overwhelm Doflamingo’s regeneration and Haki. | | Whole Cake Island | Cracker (Sweet Commander) | Tankman (Full Version) | Cracker’s Biscuit Soldiers were infinite and harder than steel. Gear 2/3 couldn’t break them. Luffy used Tankman after consuming Cracker’s soldiers to become bloated, then compressed it for a counter-attack. | | Whole Cake Island | Charlotte Katakura | Snakeman | Katakuri’s Future Sight allowed him to dodge Boundman’s slower, powerful strikes. Luffy switched to Snakeman for speed, acceleration, and unpredictable ricochet attacks to counter observation Haki. | | Raid on Onigashima | Kaido (multiple rounds) | Boundman, Snakeman, Over Kong Gun (Hybrid) | Kaido’s durability is the highest in the world. Luffy needed advanced Ryuo (internal destruction) combined with Gear 4’s power. He used Boundman for initial strikes, Snakeman for speed against Hybrid Kaido. | | Wano (Final Battle) | Kaido (final clash) | Boundman (final attack: "Bajrang Gun") | After awakening Gear 5, Luffy briefly re-entered a Gear 4-like inflated state to deliver the island-sized fist that defeated Kaido. |
It is vital to note that Luffy uses Gear 4 sparingly because of its massive drawback. Once the timer runs out, the Haki depletes, and Luffy is left unable to move for ten minutes. This tactical vulnerability dictates when he uses it. when does luffy use gear 4
. After Gear 2 and Gear 3 prove insufficient against the Warlord’s awakened powers, Luffy retreats briefly to activate this new form, which he developed during his two-year timeskip training on Rusukaina. Conditions for Use Luffy uses Gear 4 when he faces an "immovable object" or an opponent whose durability and speed outmatch his base forms. Because Gear 4 consumes massive amounts of Haki and leaves him unable to use Haki or even stand for ten minutes after it wears out, he treats it as a definitive finisher rather than an opening move. Key Appearances and Forms As the series progresses, Luffy adapts Gear 4 into different forms to counter specific fighting styles: Boundman (Dressrosa/Whole Cake Island/Wano): The default version. Luffy uses this for high-impact power and flight. It was his primary weapon against | Arc | Opponent | Gear 4 Form
Gear 4 is not a state Luffy enters lightly. Unlike Gear 2, which he can activate with a simple pump of his legs, Gear 4 requires a specific physical ritual: Luffy bites into his arm and inflates his muscles to a grotesque degree, coating them in Armament Haki. Gear 2/3 couldn’t break them