Monkey D. Luffy is the main character in One Piece who is often regarded as a fool and can not be taken seriously, but who would have thought behind all the assumption that Luffy also still has a serious side. Once in some very important scenes Luffy shows his seriousness to decide an important issue that determines the continuation of his life or the people around him, here is the discussion.
- Luffy and Usopp
The fight scene between Luffy and Usopp is one scene where Luffy shows his seriousness. The problems between the two arise when they have to decide to improve the Going Merry or just buy a new ship. Luffy, Zoro, Nami and others consider that they must have a new ship to accompany their very long journey, but Usopp has another opinion, he assumes that Merry must be repaired because Merry is the one who has delivered their journey until they can at Water Seven. Their dispute widened to cause a fight, Luffy as the captain of the Straw Hats Pirate should show his dominance as a ship leader, he also serves Usopp who has dared to challenge him for a duel.
- World Government Burning Incidents
This moment occurs when Luffy and his friends are in an effort to save Nico Robin who sacrificed himself to be brought by CP9 in order to save the entire crew. At that time Luffy decided to declare war against the World Government by ordering Sogeking (Ussop) to burn the flag of the World Government, suddenly everyone who witnessed it was shocked, how could the Straw Hats decide to declare war on the World Government.
- Incidents in the Sabaody Archipelago
Having once declared war on the World Government in Enies Lobby Luffy is now doing the same thing no less cool, Luffy who did not accept his friend Hachi shot by one of Tenryuubito, Saint Charloss. Without thinking Luffy who was emotionally immediately hit Saint Charloss with all his might. Luffy did not even care if Sabaody had to be visited by someone at that time.
- Break through Impel Down Jail
Another cool thing Luffy had done was when he went into the most horrible prison, Impel Down, to save his beloved brother Portgas D. Ace. Louise showed his courage by entering the prison alone, Luffy sacrificed everything he could do just for save his brother.
- Moments When Luffy Shows Haki Haoshoku
The cool moment shown by Luffy is that when he shows his king's haki power, like during Marineford's top bout, Luffy who sees Ace soon gets executed screaming loudly and everyone around him looks unconscious except those who have haki is stronger. The next moment is the moment when Luffy et al have to face 100,000 fish man warriors who are under Hody Jones's control, Luffy calmly advanced into the middle of the battlefield and using his Haoshoku haki, as a result half of Hody Jones's troops fell.
- Gear Forth
The moment Luffy shows the ability of the Fourth Gear is the coolest moment Luffy ever had, by turning into Gear Fourth mode Luffy managed to turn things around, Luffy who was initially overwhelmed by Doflamingo can easily turn things around and make Doflamingo not move.
Well, that's some cool moments moment owned by Luffy, actually there are many other cool moments but all can not be explained in one article only. Do not forget to follow 
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