Why did Roger tell a joke when he arrived at the last island and saw the big secret treasure?

Roger is the legendary "One Piece", not because Roger is tough, but because Roger arrived at the last island. Then Roger saw the mysterious "big secret" here, so Roger enjoyed the title of "One Piece". In One Piece 968, Yutian and Roger got their wish and reached the last island, which was Roger's long-cherished wish. Roger said it was a joke to see a big secret, so the problem came. What is this so-called "big secret"? Follow the footsteps of fans and take a look!

The biggest contribution this time is Oda. Roger begged White Beard to lend Oda to him for a year. It took him a year to find the last "big secret". Because Oda can read historical inscriptions, he needs Oda's help, otherwise Roger would not have reached the last island. After some efforts, Roger Pirates of the Caribbean finally set sail for the last island. The animation does not describe the detailed process. After some efforts, Roger pirates finally reached the so-called "decisive battle island". This place is very mysterious, and I don't know where it is at present, because there is no sign of "Final Island" on the map. With ODA's help, Roger arrived here as scheduled. He wants to find out the "big secret" of this place.

It is worth mentioning that Baki was sick and had a fever, so Baki didn't reach the last island. Jencks was arranged to stay and take care of Baki, so neither Jencks nor Baki saw the mysterious "big secret treasure". Because of this, neither of them knows what the legendary "big secret" is.

However, one of Roger's actions let us know the legendary "big secret treasure". Roger laughed and cried when he saw the "big secret". Then Roger said that the legendary "big secret treasure" was a joke. Of course, the camera doesn't tell you what a "big secret treasure" is. However, after Roger laughed, the crew of Roger's pirate group all laughed.

As can be seen from the picture, after Roger laughed, everyone laughed like odd numbers and Rowley. Because they also saw the last "big secret", but this "big secret" turned out to be a joke. Small fans also showed a "funny smile" after seeing this scene, which made people laugh and cry. So what is the legendary "big secret treasure"? In fact, Roger's words caught my attention enough to hint at what the real "big secret" is.

Roger said, I wish I could live in the same era as Joy Boy. This legendary "big secret" was left by Joy Boy, but Roger said it was a joke. From this perspective, this so-called "big secret treasure" should be a joke played by Joy Boy with future generations, which is why Roger said it was a joke. But this joke is not a simple joke, it should be an inspirational speech, or a kind ridicule, because the person who found the "big secret treasure" realized his lifelong dream. Roger saw the "Big Secret" and said it was a joke. Guess what this joke is?