After the Blood Wedding’s fiasco, Big Mom Pirates already know that Luffy, Caesar and Bege were in on it together.
Big Mom Pirates will chase them to the end of New World. As of now Caesar is all alone. Caesar is shrewd and his reasoning is simple:
1) The enemy of my enemy is my friend. Why not ally himself with the enemy of Big Mom and resist her together?
2) Joker is in prison and he doesn’t know how Kaido will react if he surrenders. He is a golden egg (SAD) laying hen, everybody wants to imprison him and make him work for themselves. What he wants is his freedom and do his experiments.
3) Bege is a better choice than Straw Hats. Bege is more brutal (like him), shrewd (not stupid like that damn Strawhat) and he might even let him do experiments on human subjects.
Of course Bege would not trust him that easily. Earlier the deal was that Caesar will get his heart back after the assassination attempt. Now there is a new deal, Bege will keep his heart until he trusts him enough. Simple.
For Bege he is getting a Logia lackey and a renowned scientist. This is an offer he can’t refuse.
Straw Hats would agree. Why? Because all they need to do is to keep Caesar away from Kaido & Big Mom. As they are going to Wano, it doesn’t seem a good idea to take a board game piece to the only man they shouldn’t give it to. That way, if worse happens, Kaido will still not get Caesar.
Some people might say what if they need Caesar for any poison gas attack Straw Hats might face against Beast Pirates? Well I doubt there will be any variation poison gas apart from the one that Jack used against the Minks. And for that poison gas Chopper already has an antidote, so he can make more.
So in conclusion, there will be a big news in News Coo. A new nakama joins the Fire Tank Pirates.
New Bounty: 400,000,000 berries
*Theory by Odin The AllFather