
Created during the Void Century, approximately 900 years ago, the character known as the Iron Giant has been resurrected and exists in this period. Although he resembles a robot, he may possess the soul of someone from the past, allowing him to feel emotions like a human. This was confirmed when the Iron Giant apologized to Joyboy just as he was coming to life.
However, looking back in time, this Iron Giant has the ability to fight Joyboy for the sake of the World Government. After his defeat, it is likely that he was disassembled or lost somewhere in the depths of history. Around 200 years ago, the Iron Giant reappeared, climbing the Red Line and greeting the Celestial Dragons in Mary Geoise.
Just when things seemed to get worse, he ran out of power and fell silent. The World Government wanted to eliminate him, but scientists researching him found ways to hide the Iron Giant, ultimately leading him to Egghead Island, where Dr. Vegapunk is currently conducting his experiments.
Vegapunk has made efforts, but he has been unable to find new energy sources for the Iron Giant. However, Luffy’s appearance on Egghead has drastically changed the game, and it seems that the Iron Giant is about to play a critical role from now on.
The Iron Giant Awakens Alongside Gear 5 Luffy

The true essence of the Iron Giant coincides with Luffy’s arrival on the island. When Luffy faced Kizaru, the emotions that arose within Luffy awakened the Iron Giant, who had been dormant for 200 years. After that, when Luffy activated Gear 5, the Iron Giant rose once more.
Now, Luffy decides to escape from Egghead along with his companions, and that is when we see the Iron Giant crossing the sea of flames. The first thing he does is apologize to Joyboy, which suggests a special connection he has with this character.
Even though he is a robot, the Iron Giant is fully autonomous and has the capacity for sensation. It appears that there is a strong bond connecting him to Luffy, possibly related to the character of the Buccaneer, similar to Kuma in many aspects.
What is the Role of the Iron Giant?

The pressing question that many people are wrestling with right now is: “What is the role of the Iron Giant?” All signs point to him being the embodiment of Joyboy, created by the people of the Ancient Kingdom. His first words after awakening were an apology to Joyboy. His role may involve helping fulfill the legacy of the D. lineage or aiding someone in completing this mission. Joyboy is inherently the one who represents this.
Then we have the story from 200 years ago, when the Iron Giant climbed the Red Line and attempted to invade Mary Geoise. Perhaps he did not intend to invade but was trying to reach the depths of history, similar to what Bartholomew Kuma is currently doing.
At this point, the Iron Giant has risen again, likely to assist Luffy’s team in escaping from Egghead. And who knows, we might even learn more about his history, his objectives, and the reasons behind his climb up the Red Line 200 years ago.