At the Battle of Marineford, a sharp blade suddenly pierced Marine Admiral Sengoku through the chest from behind.
As Marines and pirates alike stared in utter shock, Lieutenant General Yaen, the always laid-back and mild-mannered "Navy Hero" who called himself a "Buddha-style" person, pulled back his blade and slowly rose into the air.
"The eight hundred years of history with no one seated upon the World Government's Empty Throne are about to end. From now on, I shall stand above the heavens."
Yaen looked down at the world below with a perfectly calm expression and made his silent declaration.
"Of course..."
"From this moment on, all the evil in the world will be mine to command!"
(A synopsis with a twist...)