Of the four possibilities that Duniaku.net wrote yesterday, Kaido attacking the Reverie Council is the worst and terrible.
Teach can still control himself while in action. (The proof he did not attack Luffy first in Impel Down, because Luffy is not the target). The Dragon Crew is basically filled by good people like Sabo and Koala, who will make sure the casualties beyond their targets are minimal.
When Kaido attacks the Reverie Council, nothing is safe. Starting from the event's escort, the host, until all the guests present will be threatened.
More details, here's a discussion of the bad things that will happen if Kaido attacks the Reverie Council.
There Can Be a Good Duke Who Threatened His Life
Among the Reverie Council participants, there are obviously evil people like Wapol.
However, of all the people already known by OPLovers, more and more good rulers are present to the event. Call it Vivi and Riku Dold III.
Indeed, if Kaido attacked the Reverie Council it would have been most of its royalty royalty whose name was not even known. But fan favorite nobles like Vivi and his father will also be in serious danger.
In fact, given what kind of work Kaido might have, some of them would not have escaped from the battle alive. The authors are especially concerned about the good nobles who are willing to sacrifice themselves if the situation requires, such as Nefertari Cobra.
If Kaido wants to make the biggest war the world has ever witnessed, then his best choice is to attack the Reverie Council.
If he attacked his fellow Yonko, then in the end the conflict will only be on him and the Yonko he attacked. He attacked the Navy, like Whitebeard? Fighting will only occur between him and his fleet against the Navy plus the Shichibukai.
But if he attacks the rulers of the Reverie Council, suddenly those involved are not just Yonko and the Navy. Other countries whose ruler he attacks, or even kill, will try to target his head too. On the other hand, there may also be countries that decide to support Kaido to find it safe not to be destroyed.
If it were so, there would have been a mighty war of warfare whose victim of his soul might even exceed Marineford.
Another bad thing that can happen if Kaido attacks Marineford can you read on the second page!