Chapter 644

Chapter 644 is called "To Zero".

Cover Page
From the Decks of the World Vol. 27 - "Jaya - South Bird ♥ North Bird → Western Bird & Eastern Bird".

Short Summary
Noah continues falling toward Fishman Island while a flashback of Hody's appears. In the Fishman District, Hody and the New Fishman Pirates officers were taught as kids that the humans are an inferior species and they should be punished by heaven. The flashback moves forward in time when Hody was an Ammo Knight and he and his crew commit crimes, celebrate the death of Otohime, and start producing Energy Steroids and the flashback ends. Fukaboshi gives an emotional speech to the whole island about the cause of this event and begs Luffy to create a new beginning. Luffy then tells Fukaboshi to leave everything to him and his crew. After the discussion ends, Hody catches up to Luffy and Shirahoshi and Luffy punches him with a burning fist.

Chapter Notes

 * Hody's appearance continues to mutate further.
 * Luffy does a new attack called Gomu Gomu no Red Hook.
 * There are north birds, east birds, and west birds in addition to south birds.
 * The past of the New Fishman Pirates is revealed
 * This is the first time ever that Luffy has used a fire based attack.