The Devil Fruit system remains one of the most powerful and crucial elements in the world of One Piece. As the story deepens, creator Eiichiro Oda has unveiled incredibly strong Devil Fruits, some even regarded as “God Fruits” in legend. Now, with the latest developments in chapter 1156, Oda officially confirms the existence of two legendary-level Devil Fruits. One of these is currently on Elbaf, and both are connected to the infamous pirate Rocks D. Xebec.
Rocks plans to overthrow the World Government

In One Piece’s Final Saga, Rocks D. Xebec has become a pivotal figure, especially in the Elbaf arc. Known for his irresistible charisma and thirst for power, Rocks aims to dominate the world. To achieve this, he must defeat Imu, the supreme figure of the World Government.
Flashbacks reveal that when Rocks invaded Mary Geoise 56 years ago, he did not confront Imu directly because he lacked the means to overthrow him.
However, over the years, Rocks has been quietly preparing his plan and seems to have completed it. Around 44 years ago, he turned Pirate Island into his base, amassed enormous wealth from the Government, and built an incredibly powerful force, making him nearly unbeatable. Most importantly, his plan to overthrow Imu is ready, and the key lies in two uniquely powerful Devil Fruits.
Rocks reveals two legendary Devil Fruits needed to topple the World Government
According to Rocks, completely overthrowing the World Government requires two legendary Devil Fruits. Given his vast knowledge of history and world secrets, this information carries great credibility.
Rocks further states that one of these Devil Fruits is on Elbaf. As fans know, Elbaf has a Devil Fruit passed down through generations and guarded carefully, awaiting the arrival of the destined Warrior.

No need for much guesswork, the first Devil Fruit mentioned is the Hito Hito no Mi, Model: Nika. This fruit was once on Elbaf before being stolen.
The other Devil Fruit, most likely, is the Yami Yami no Mi (Darkness Fruit), currently held by Blackbeard, who is rumored to be Rocks’ son.

Interestingly, Rocks seems to want Harald to consume one of the two fruits (likely the Nika fruit). At the same time, Rocks may intend to eat the other himself. This hints at an exciting scenario: Rocks once planned to team up with the Nika fruit user to defeat Imu. This could set the stage for a dramatic three-way battle between Luffy (Nika fruit user), Blackbeard (Yami Yami no Mi user), and Imu in the future.
The events unfolding in the Elbaf arc are bringing One Piece closer to the world’s deepest secrets, promising an unpredictable conclusion.