The Haggadah is a story retelling the liberation of the Jews from Egypt with Moshe as the protagonist and hero. The Pharoah was the oppressive ruler of Egypt at this time and is responsible for the events that took place. There was slavery and mistreatment that only ended with Moshe's bravery and belief in God . 

One Piece is a surprisingly similar story that incorporates the elements of tyrant like rulers, oppressed people, and supernatural elements being used throughout. Some of the major themes are liberation and freedom, which are the same as the Pesach story.

Luffy is One Piece's paralell to Moshe and is the main liberator using everything he has to fight against opression. He literally is close to death nearly everytime he saves a nation. 

haggadah Section: Introduction