In chapter 803 Koala says that the weapons they got from Dressrosa contains a unique metal.
Sake Tekkō or sake-steel-ore.
These metals are mined only by a few countries, so the Revolutionary Army can use this information to get closer to the mastermind behind the making of this weapon.
So, who is the mastermind behind the making of this weapon?
The answer lies in the Cover Story Chapter 701.
Before going further, I suggest you re-read this Cover Story starting from chapter 674.
in Chapter 701 Caribou discovered a weapons factory in the island. If you notice further, the island is the same island that is visited by X Drake in chapter 595.
In the chapter 595 the "mountain" seen in the distance still being built, whereas when Caribou come there the "mountain" is already completed.
When X Drake first there he met with the island guard, Iron Boy Scotch. And indeed, finally Scotch and Drake also seen there when Caribou in the island.
On the island there was an uprising led by Gaburu. People who rebelled were workers at the weapons factory, who eventually the rebellion stopped by the guard island, Scotch (chapter 704).
Ultimately Caribou, whose face is similar to the Chairman of the Revolution there, "absorb" the factory into his body so that the workers can be free. But then he was defeated by Drake (chapter 725/727).
The meaning is, Scotch and Drake are the keepers of the island. Keeping the threat from outsiders and also rebellion from within. The matter is, if they are the guard, who is the owner of the factory?
Scotch have said very clearly about this in Chapter 595, this island is one of the favorite island of Kaido!
Yes, I'm sure Kaido is the owner of this factory.
It all makes sense when we connect with the weapons Revolutionary army acquired in Dressrosa which belong to Doflamingo. We know it is true that Doflamingo is a Kaido's business partner. If Doflamingo gives SMILE on Kaido, what Kaido give to Doflamingo? Weapons!
If so, the direction intended by Dragon cs in the Revolutionary Army to locate the origin of the weapons will end up in Kaido. I'm sure Kaido still had plenty of other factory, so the Revolutionary Army will try to destroy all of them, or just beat Kaido in particular.
Luffy itself has become a target of Kaido when he destroy the most important business partners of Kaido. Of course Kaido's anger will culminate in a fight between the two pirate.
But with the Revolutionary Army now also has an agenda with Kaido, I could see them going shoulder to shoulder beat Kaido. May not be frontal, or maybe just in the forefront part of the destruction of the weapons factory, but I'm sure the Revolutionary Army will help the Straw Hats to defeat Kaido pirates.
Or do you want to see father and son, Luffy and Dragon, work together to defeat those who can not die even by himself?
Brace yourself.
(sorry about my English)