The Straw Hat Grand Fleet is a fleet formed by seven pirate crews who vowed to serve under Monkey D. Luffy and the Straw Hat Pirates.
Formed from various powerful crews who managed to succeed in the New World, and the representatives and some other members have been prime contestants of the Corrida Colosseum, the crew is very powerful indeed. In sheer numbers, they have a grand total of 5640 people(not counting the Straw Hat Pirates) from various tribes and races, being quite versatile in strength and other attributes.
Five of the seven leaders were powerful enough to defeat executives of the Donquixote Pirates.
Putting the combined known bounties of all of the “Straw Hats” together (both main crew and Grand Fleet) comes to a known total of at least 4,183,000,100 Berries.
The existence of the Grand Fleet was a key element in Luffy becoming the “Fifth Emperor of the Sea”.
The 5,640 Straw Hat Grand Fleet crew members may refer to Luffy’s Gomu Gomu no Mi (“5+6 = Go+mu”).
Right now, the World Government seems to want to go full force on their imposition over Wano, despite what the little fleet they have outside Wano would suggest for now.
It would take a power move by Luffy to truly establish Wano as an open country in the long run and what better way to do it than his Grand Fleet coming in and flexing in on the World Government’s armada?
Can’t wait to see them in action!