When Admiral Kizaru first arrives in One Piece, it's akin to the rest of the cast being touched by the hand of an indifferent god. Kizaru doesn't seek revenge, nor any passionate ideal. Instead, he's the cold, superpowered tool of bureaucracy, a government man here to essentially balance the budget. And that means ripping through everyone that stands in his way. The arc in which he initially appears, Sabaody Archipelago, is an inflection point in the series: The Straw Hat crew isn't just defeated but forcibly separated by obstacles that they never really stood a chance against. And Kizaru is a prime example of that overwhelming might.
Now, years later, Luffy prepares to take on Kizaru on Egghead Island. Luffy's gotten much stronger since Sabaody, while Kizaru has remained a nightmarish force for the World Government. There will be more emotionally-charged battles in the future, for sure, but there are very few that will match the importance of the upcoming fight.
