A little bit of information beforehand if you don’t know the story of the four Horsemen. The four Horsemen of the Apocalypse are the heralds of doomsday. Every Horseman stands for one calamity in this world: War, Pestilence, Famine and Death.
We know that Kaido’s three Commanders are called Calamities too. Kaido + 3 Calamities = 4 Horsemen of Apocalypse. This would explain, why he wants to declare the greatest war the world has ever seen. He wants to see the Doomsday for the OnePiece-World.
Let’s take a closer look to what we can refer from the biblical story to One Piece.
The three Calamities War, Pestilence and Famine: I think these are the three Commanders of Kaido.
1. In my opinion, Jack stands for the Horseman War. We see that Jack is destroying everything just with a wipe of his trunk in his Mammoth form.
2. The second Commander will be themed around Pestilence, maybe he got some kind of Devil Fruit where he can give some kind of disease to everyone he touches. That is why i think Chopper will be the unsung hero of that arc. He will be there to cure those diseases and bring him a big step forward towards receiving his dream of healing all diseases.
3. The third Commander will be some kind of Famine – maybe he got the ability to dry out any kind of land (like Crocodile could do with his Suna Suna no Mi) or he got some kind of aura, that everything close to him will wilt and spoil.
Concluding this, we got 3 of the Four Horsemen, which already are totally overpowered. But then there is Kaido next. I think Kaido is the biblical character Death.
From the Bible we know that Death can’t be killed in any ‘normal way’ – he can only be killed by his own scythe. This is why Kaido can’t be killed, even when he should get executed several times or jumped from a Sky Island. He just don’t know it, that he needs his own scythe. Also the Death is some kind of the leader of these four Horsemen. Furthermore in the biblical texts there are some more possible connections:
” I watched as the Lamb opened the first of the seven seals “ – This can also be some kind of foreshadowing from Oda. Did you notice that these Beasts Pirates got horns like goat or LAMBS? And that there is a guy called Sheepshead?
” When the Lamb opened the fourth seal, I heard the voice of the fourth living creature say, Come! I looked, and there before me was a pale horse! Its rider was named Death, and Hades was following close behind him. They were given power over a fourth of the earth to kill by sword, famine and plague, and by the wild beasts of the earth. “– there are two possible connections:
“They were given power over a fourth of the earth” – He is one of the Yonko and possess one of the four Road Ponyglyphs – means he/ his crew owned one fourth of the secret behind Raftel (the secret behind the truth at all?)
“to kill by sword, famine and plague, and by the wild beasts of the earth. “ – He isn’t called Kaidou of the Beasts for no reason.
*Theory by Sero678