The flashback is short,
King and Kaido are in a research facility.
Kaido: I'm leaving here to create a pirate crew. Will you accompany me?
King: Are you going to change the world?
Kaido: I'm the only one who can change the world.
King and Kaido escape from the research facility and see it burning
King and Kaido are in a research facility.
Kaido: I'm leaving here to create a pirate crew. Will you accompany me?
King: Are you going to change the world?
Kaido: I'm the only one who can change the world.
King and Kaido escape from the research facility and see it burning