D: Oda sensei, hello! The young mermaids in the towns and coves are all beauties, aren’t they? So, the question is, what did Ms. Kokoro look like when she was young? Please draw me a picture!!

O: Sure thing–. That’s it for this SBS~. See you in the next volume!!

Everyone remembers this moment in the manga

The legendary introduction of the strongest creature alive KAIDO!!!!
And everyone’s first thoughts were “the Kidd alliance is about to get destroyed”
And later people thought “no, they will start an alliance to target Shanks”
hhmmmm, not bad conclusions,although I think it’s something different
I think that Kaido and kidd met each other way way before Kaido fell into the base
Basically my theory is: Kaido and Kidd = Shanks and Luffy
Now to convince you all to agree with me

1. Kidd, Law and Luffy

Now, since this epic moment of Kidd, Law and Luffy fighting side by side people wouldn’t argue that these three supernovas will be the leading force of the new generation
now I want to point out something Law and Luffy had similar in their flashbacks
powerful pirate influences and being given devil fruit by them
Luffy—> Shanks and got the gomu gomu no mi from him
Law—> Doflamingo/Corazon and got the ope ope ni mi from them
So both of them had powerful pirates to influence them and give them devil fruits….interesting
Also, I don’t think people will argue that Kidd and Luffy being heavily paralleled and Kidd usually being a step ahead of him
So if Kidd were to have a strong pirate influence that gave him a devil fruit wouldn’t it make sense for it to be a Yonko like Luffy had….but wait
Kidd attacked Big Mom’s ships so I doubt it could be her
Whitebeard, sadly, is dead
Blackbeard just became a Yonko
and Shanks had Luffy
so that’s right, Kaido seems to be the only one left
……not convinced? Let’s continue

2. Why would Oda have Kaido fall into Kidd’s base?

to beat everyone in the alliance…….hhhmmmm, but why not do it like he did with Blackbeard and Bonney
he showed the blackbeard and Bonney situation after the Bonney was defeated, so couldn’t he have done that and make Kaido’s reveal 10x more awesome if that was his intention the whole time, so I doubt that is the answer

for Kaido to get beaten….this makes a little more sense, but wouldn’t this basically be a gaint fuck you to all the work Luffy and his crew has been trying to do especially with the recent chapters….I don’t think Oda would do this to his main characters so let’s try a different answer

for Kaido to ignore them and walk away……then why land in Kidd’s base….unless the hole he made will be an important plot point for later I doubt this is it

for an alliance…….this could happen but so far….Kidd’s and Kaido’s personalities don’t show this happening anytime soon especially since Kaido is a Yonko….unless something is missing from this answer… like

reuniting Kidd and Kaido and possibly having them work together……if Kidd and Kaido already know each other then working together wouldn’t be out of the question and it explains why Oda had him fall in front of Kidd…..so this does seem to make sense

3.Kidd post-timeskip
in case you haven’t noticed, Kidd has been in every arc since the timeskip
Fishman Island:
Mentioned to have destroyed some of Big Mom’s ships
Punk Hazard:
Shown to be involved in the underworld
later, shown making his own alliance
Dressrosa:
Shown to be targeting Shanks
later, the Kaido incident

So yeah, it seems that Oda is hyping Kidd up to do some big things, he’s even in a similar situation to Luffy (messing with Big Mom then targeting a different Yonko (by messing with Big Mom, I mean Luffy threatening her not the Sanji stuff)) so Oda would most likely continue with hype, but if wanted Kidd to defeat Kaido he wouldn’t do it off panel like how he showed Ace VS Blackbeard so how can he continue the Kidd hype….
by having Kidd and Kaido sitting together talking about future plans or even reminiscing about the past

4. So, if you are still not convinced I have one crucial piece of information to show
Do you remember this?

That’s right, Kidd randomly crucifying people
and what do we know about Kaido’s crew members?

They believe in crucify and chill
coincidence…….nope
Epic Oda foreshadowing the relationship between Kidd and Kaido
5. Conclusion
What do I think happened after the fall?
hhmmm, maybe something like this

(a yelling match between Kidd and Kaido)
Kidd: DAMN YOU KAIDO, WHAT ARE DOING FALLING INTO MY BASE
Kaido: THEN GET YOUR BASE OUT OF THE WAY OF MY SUICIDE ATTEMPT
Kidd: GO SUICIDE SOMEWHERE ELSE
Kaido: NO, GO MOVE YOUR BASE SOMEWHERE ELSE

Apoo and Hawkins: …….uuuummmm
(then Killer explains the relationship of Kidd and Kaido)
Then they work together on something whether it defeating Shanks or something to do With Wano

That’s the end of my theory so

*Theory by PlatinumRoger