Monster trio of Straw hats

The Moster trio in Straw hats pirate is refered to luffy , zoro and sanji.

Nami is the one who dubbed them the Monster Trio because those three have astonishingly inhuman strength. They were crushing stones, breaking mountains, wrecking Pacifistas in a single attack, etc. 

Mugiwara Luffy is the Captain of the Straw hats pirates where as Pirate hunter Zoro is the Vice-captain. Black-leg Sanji is the cook of the ship. They are the strongest members of Straw hat pirates.

Monkey D. Luffy, also known as "Straw Hat" Luffy, is the Captain of the Straw hat Pirates. Luffy is a young boy who acquires the properties of rubber after accidentally eating the supernatural Gum-Gum Fruit. His goal is to become the King of Pirates and is on the race of finding One piece in the pirates world.

Roronoa Zoro, also known as "Pirate Hunter" Zoro, is the combatant of the Straw Hat Pirates, and one of their two swordsmen. Formerly a bounty hunter, he is the second member of the crew and the first to join, also known as Vice-captain of Mygiwara Kaizoku dan. With an aim of being the Top swordsman to ever exist , he is in adventure with Strawhats finidng strong swordsman and defeating.

"Black Leg" Sanji, born as Vinsmoke Sanji, is the cook of the Straw Hat Pirates. He is the fifth member of the crew and the fourth to join, doing so at the end of the Baratie Arc. Women and cooking is his only interests. His dream is to find All blue. 

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