Sanji is a member of the Monster Trio, which consists of the strongest three fighters within the Straw Hats. He joined the crew all the way back in the Baratie arc. Initially, Sanji did not want to leave the restaurant because of Zeff, but after talking to Luffy for a while, he had a change of heart.
Ever since joining the crew, Sanji has been indispensable. Luffy wanted Sanji to join the crew because the latter was an incredible cook, but he has proven that he is just as talented as a fighter. Not many characters inOne Pieceare as versatile as Sanji, which puts him in a very special group. Over the course of the series, Sanji has helped the Straw Hats in their adventures. With so many lifesaving interventions, Sanji is undoubtedly one of the most clutch characters inOne Piece.

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Sanji’s Intelligence
The biggest difference between Sanji and the other two members of the Monster Trio is their intelligence. Luffy and Zoro are undoubtedly more powerful physically, but Sanji stands out with his cleverness. On various occasions, Luffy and Zoro have taken the physical approach even when it wasn’t the best option.
On the other hand, Sanji always looks for the best option that will ensure the safety of the crew. With his keen perception, Sanji was the first person to realize why Law wanted to make an alliance with Luffy. During the Zou arc,he used his Observation Hakito sense Nekomamushi outside, and then he threw the rest of the crew out of Bege’s body to keep them safe.

Pre Time-Skip Feats
Sanji has a history of saving the crew from danger. During the Alabasta arc when most of the Straw Hat crew was captured by Crocodile, Sanji used his wit to outsmart Crocodile and lured him out of Rain Dinners, so that he could free the Straw Hats and prevent them from being eaten by bananawani. Then in the Skypiea arc, the Straw Hats were fighting against Enel, who possessed the Goro Goro no Mi. With his devil fruit, it was almost impossible for anyone to land an attack on him. Luffy was the only person, whose attacks could make contact with Enel.
It was mainlybecause his “Gomu Gomu no Mi” was a direct counterto Enel’s lightning. During their fight on the Ark Maxim, Usopp and Sanji snuck aboard to save Nami from Enel. While Usopp was trying to help Nami, Sanji went to destroy the engine of the Ark Maxim which brought the Straw Hats more time. When Usopp was about to be struck by Enel, Sanji kicked him towards Nami and saved him.

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Once again Sanji showed his brilliance when he figured out the whereabouts of Nico Robin. Sanji found out that there was one train leaving before Aqua Laguna, so he left a note and followed the train. When the crew reached Enies Lobby, they had to fight the members of CP9 to save Robin. As the arc continued, Usopp was left to face Jabra. The CP9 member was a lot stronger than Usopp, and at one point it seemed that the Straw Hat sniper would die.
Luckily for him, Sanji arrived in the nick of time and kicked Jabra. This allowed Usopp to get back to safety and snipe Spandam. After Luffy defeated Lucci, there was a Buster Call, and given the condition of the crew, there was no way that the Straw Hat Pirates could fight. However, Sanji had already pulled the switch that controlled the Gates of Justice. This caused the Gates of Justice to shut down and preventedthe Marines from followingthe Straw Hats.
Post-Time-Skip
Sanji’s exploits continued even after the crew entered the New World. When the crew landed on Punk Hazard, Sanji was the one, who saved Kin’emon’s body, and it would be fair to say that this event effectively started Luffy’s journey to take down Kaido. Sanji also saved Tashigi from being killed by intercepting Vergo’s attack.
At Dressrosa, the crew was divided into two groups, Sanji’s group remained on the Thousand Sunny. Nami and a few others, who were also on the ship were shouting which drew Doflamingo’s attention, and he immediately gave up pursuing Law and started moving towards the ship. The crew had absolutely no chance of surviving, but Sanji was there to save the day. He used his attacks to hold off Doflamingo for a while, and it was enough for Law to get back and lure Doflamingo away.
His biggest involvement after the time-skip came duringthe Wano Country arc. After Momonosuke had been captured by the Beasts Pirates, Kaido planned to execute him on the Live Stage. The execution would have served as a message to all the rebels, and it would have undoubtedly crushed their spirits.
Shinobu tried to save Momonosuke, but she failed. With the help of his raid suit, Sanji managed to save Momonosuke, effectively preventing the future shogun of Wano from dying. If Momonosuke had been killed, the alliance would have fallen apart as they would have lost their future leader. In addition to preventing Momonosuke’s execution, Sanji also saved O-Tama, Chopper, and even Zoro. All these feats make it pretty clear that among the Straw Hats, only Luffy is more clutch than Sanji.
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