In Episode 272, Luffy activates Gear Second for the first time on-screen. The key mechanics shown:
This episode marks the first time we see the lightning-fast "Gomu Gomu no Jet Pistol". gear 2 episode number
Luffy uses his legs to pump blood faster through his body. In Episode 272, Luffy activates Gear Second for
Luffy was getting pummeled. He realized that his base form—while strong—lacked the speed to hit these opponents. He needed a way to match their velocity. In Episode 272