Additionally, Queen calls King “a torture loving pervert” and while this might as well be just bickering between the 2 and not something that is true, it could further hint towards his previous role as a guard in Impel Down since it is infamous for its torture. Shiryu would just cut down prisoners for fun while Magellan would leave them poisoned to die. Seems to me like a bunch of torture-loving people. King would torture Kaido and try to break him but to no avail. Kaido would just take it no problem. This would make King respect Kaido’s strength enough to want to follow him as his captain which was recently revealed to be the case in the Vivre Card.
Queen the Plague
In Chapter 1007 we learned from CP-0 during one of his captures by the Navy, Kaido was experimented on by Vegapunk who successfully managed to clone his Devil Fruit (the same one that Momo ate). We also learned during Whole Cake Island that Judge Vinsmoke worked together with Vegapunk for a period of time which would explain the cloning technology and how Judge seemingly infused his children with Devil Fruit Powers through “Lineage Factor”.
In Chapter 1017 it is revealed that Queen is a former member of MADS, the scientific research team that included Sanji’s father Judge, Vegapunk and Caesar Clown. One of their most notable accomplishments includes the discovery of the Lineage Factor, also known as the “blueprints of life itself”.
Furthermore, there have been multiple mentions of Vegapunk during Wano and there is a certain focus on him. He was name dropped by CP-0 and how he experimented on Kaido, Orochi requisted from CP-0 to meet him and probably most overlooked thing, Tama’s Teapot. Even as far as Alabasta, we learned that objects can “Eat” Devil Fruits. Then we learned that the one who manage to do this was Vegapunk and here in Wano, we have a Teapot that ate a Tanuki Devil Fruit. So it’s highly likely we can expect connection between him and Beast Pirates and Queen fits the bill.
Jack the Drought
So we know Kaido was experimented on by Vegapunk and the most likely location where this took place is Punk Hazard. Punk Hazard has been a place where Vegapunk performed his experiments alongside Caesar Clown until few years ago when Caesar fucked it all up. King was sent from Impel Down to overlook his experimentation on Kaido and to make sure he doesn’t escape.
We also know that The Navy has obsession with Ancient Giants which is evident by the failed clones that were made on Punk Hazard. Those clones are known as the Numbers. They are currently part of Kaido’s crew. Interestingly enough, Kaido shares a lot of similarities with the Ancient Giants (his horns mostly) leading a lot to speculate he could be their descendant. We now “know” he is from an Oni race which might be the same as Ancient Giant race. This could also be a reason as to why the Navy would want to experiment on him since he might be last of his species like King, and why he is known as a “Strongest Creature” and not “Strongest Man”.
The other obsession that Navy has is with the regular giants. Giants are considered to be very powerful warriors and the Navy always wanted such strong force on their side. The only issue is that they couldn’t get any until Mother Caramel came along. So what did they do? They experimented with gigantification even before Big Mom tasked Caesar with it so she could have Giants in her “Utopia”. One product of these experiments is Jack.
We know from Caesar’s experimentation with gigantification that it works only on kids, or at least it is most effective when it comes to kids. Well Jack is currently 28 and that Jack wasn’t present when Wano was being conquered by Beasts Pirates, so somewhere between the 20 years Jack joined them.
Kaido said he hand-picked Jack to be his All-Star. I like to think that Kaido saw Jack when he was visiting Punk Hazard to buy The Numbers and in Jack, who was being experimented on, he saw himself when he was younger. Jack and Kaido look alike a lot, especially their body shape, and that coupled with him being experimented on just like Kaido was experimented on made him want to recruit Jack.
We also know that to be considered a giant you need to be at least 12m. Jack is 8.3m tall so not quite there which would fit the pattern of “failed experiments” (The Numbers, Momonosuke’s Devil Fruit, Dragons) that seems to be the case when it comes to Punk Hazard. “But why can’t he just be a Hybrid of Giant and something else?” well because Jack is confirmed to be full blooded Fishman. No race mixing involved.
So, in short, when Kaido got captured by the Navy he was originally sent to Impel Down where King was a guard (Vice-Warded/Warden). Shortly after, he was transferred to Punk Hazard where Vegapunk alongside Queen did experiments on Kaido because he has blood of the Ancient Giants/Oni inside of him. King was sent to oversee the experiments so that he doesn’t escape but was eventually the one responsible, alongside Queen, for his escape. Few Years after his experimentation on Punk Hazard, while looking to buy Numbers, he met kid Jack who was being experimented on with gigantification.
This would fit the bill of only 2 people escaping Impel Down before Luffy (Shiki and Marley) as Kaido would have escaped while he was being held at different location.
*Theory by The_Biggest_Wheel
