Piece 4th Gear — One

"Unlike Gear Second (speed) or Third (bone balloon), Gear Fourth is muscle balloon. Luffy bites his arm, blows air into his muscles, and coats them with Busoshoku Haki. His body becomes hyper-resilient and hyper-elastic—but he's not just big. He's constantly bouncing because his rubber properties are maxed out."

"Gear Fourth showed Luffy evolving from brute force to tactical genius. What's your favorite form? Comment below." Article / Blog Post (Key Sections) Title: One Piece Gear Fourth Explained: Forms, Powers, and Costs one piece 4th gear

Luffy inflates his muscles by blowing air into his arm (not bones like Gear Third). He then coats his entire body with armament Haki, creating a super-dense, hyper-flexible form. The compression from his rubber allows for spring-loaded attacks with massive recoil. "Unlike Gear Second (speed) or Third (bone balloon),