In Dressrosa Luffy enters the Corrida Colosseum Tournament as the 556th contestant “Lucy”, registered with the ‘0556’ number on the back of his shirt.
![](http://www.opfanpage.com/wp-content/uploads/2018/01/797d3d1e2710625b816e44be3fe8dc8c5887c92b4a3539be7e8a731c80acf45f_1.jpg)
556 is the number of the chapter where Luffy has arrived to Marineford in order to save his brother Ace .. and here he tries to save Ace’s Fruit.
![](http://www.opfanpage.com/wp-content/uploads/2018/08/1-22.jpg)
Also there’s another reason as to why Oda chose this particular number. Luffy was born on May 05 and 5-6 means go-mu in Japanese.
ODA is really a genius!