One Piece Chapter 6, page 8-10: Chapter 6: Number One

Luffy's sweeping leg connects solidly with the Marines, sending them flying through the air in all directions. The sheer force of the impact is emphasized by a massive "!!!!" sound effect as the soldiers are completely overwhelmed by the rubber man's attack.

The Marines crash heavily to the ground, completely defeated. Captain Morgan watches in utter shock, gasping, "!!?" Zoro, staring at Luffy's leg as it snaps back to normal, asks in amazement, "WHAT THE DEVIL ARE YOU!?" Koby is equally thrilled, cheering, "WOW! HE'S INCREDIBLE!" Luffy smiles proudly, retracting his leg, and happily declares, "I'M A......RUBBER MAN!!!

The defeated Marines lie groveling on the ground, completely terrified. They cry out, "A RUBBER-MAN!?" and "CAPTAIN!! THEY'RE TOO MUCH FOR US!!" Another despairs, "IT'S HOPELESS! WE CAN'T FIGHT A RUBBER MAN......AND THAT DEMON RORONOA ZOLO AT THE SAME TIME!!" Meanwhile, Luffy and Zoro stand side-by-side in a powerful, confident pose, with Koby watching them from behind as a dramatic "DA-BOOM!" sound effect frames the heroic duo.