TransformationFirst seen: Episode 726

Gear Fourth

Gear 4th / Fourth Gear

ギア4

Used by Monkey D. Luffy in One Piece

Description

Luffy coats his arm in Busoshoku Haki (Armament Haki) and bites it, inflating his muscles while infusing every fiber with Haki. This creates a massive, muscular form with extraordinary offense and defense. Luffy gains flight capability and his attacks become coated with Haki by default. Developed during his two-year training on Rusukaina island fighting enormous beasts.

Power & Effect

Extreme offense and defense; flight capability; all attacks Haki-coated; three distinct sub-forms

Trivia & Notes

  • Three known forms: Bounceman (default), Tankman (endurance), Snakeman (speed)
  • Cannot use Gear Fourth indefinitely — Luffy's Haki runs out after a set time
  • Developed specifically to defeat the massive animals on Rusukaina island

More Monkey D. Luffy Techniques

Technique information is collated from community sources, fan wikis, and the official series.One Piece content is the property of its respective creators and studios.