One Piece Chapter 18, page 21-22: Buggy, 'The Clown Pirate'

Buggy is shocked to hear the name, stammering, 'WHAT? THIS IS SHANKS'S HAT?! I THOUGHT IT LOOKED FAMILIAR...!!' He spits on the hat and reveals, 'ME AND THAT GUY USED TO BE IN THE SAME PIRATE SHIP. TO REPHRASE THAT... HE WAS MY COMRADE WHEN WE WERE STILL PIRATE TRAINEES.' Luffy is stunned, asking, 'YOU SAY THAT HE WAS YOUR COMRADE!? SHANKS IS A GREAT MAN...' Luffy charges at Buggy, who quickly splits his head from his body, shouting, 'BARA BARA EMERGENCY ESCAPE!!

Luffy screams, 'DON'T COMPARE YOURSELF WITH HIM!' and delivers a devastating, full-force punch straight into Buggy's face with a loud 'CRACK!!' sound effect. The impact sends Buggy's detached head flying backward, his face completely distorted in pain.