Well, so many theories. I think I'm gonna post my opinion on some of them:
"Law took luffy's heart!"
"The 100 hearts were beating!"
Both this theories require one simple question to be plausible… Can Law extract beating hearts?
I think he can. If your body functions normally without your head. It should function just as normally without your heart. The heart would receive the blood, and pump it to the rest of the body. That's how Leg's and Head are receiving their blood, the heart is still inside "Torso". So yeah I think Law can have done it.
Now for Luffy's heart theory, I'm not a big fan. It's totally plausible, but any plot point it could create would be extremely annoying. Unless Luffy beats Law shitless before he can even crush is heart. That would be kind of good, but I don't really think so.
The 100 hearts were beating. That I have to say I'm agreeing with it 80%. Just plain dead heart's is not that interesting. Many people send the heads of fallen pirates. Same thing. Now beating hearts has a lot of possibilities. Better than having those pirates DEAD, is having them as slaves. Whenever they try to rebel you just threaten to crush their heart. It even explains why it got Law the position. Having Law against the government would be dead, but if he has total control over 100 (suposedly powerful) pirates, that's a different story.
But the theory I liked the most was "The 100 hearts is a lie!!"
I love this theory because of the possibilities. It's just plain interesting.
Let's say Law is a doctor, wanting to conduct experiments. He talked to a contact inside the world government, and made an agreement to make him a shichibukai. Obviously those experiments are way to dark, so they decided to spread a lie, which fits with Law's reputation, and would bring him the same position.
It's almost fan-fiction like, but I just love it. It would add depth to the world government. Depth to Law's character, and wouldn't be just a random act of terror. Me likes!!
Let me remember more theories...
Leggy is the samurai's son.
I don't know. I'm not willing to assume they're the samurai's leg just yet. He commented on the torso, but not on his leg's. Also, Torso was pretty strong, and willing to attack, legs on the other end just kicked once and run away. I know legs can't old swords, but such a strong samurai has to have strong legs. Furthmore, Leggy is much more quiet than headdy. Maybe he can only talk when he has gases... it's hard to fart when we want. :ninja:
Hmmm Centaur boss is brown beard. I don't think so. Brown Beard was not a centaur... that's one.
Centaur boss is a giant. Well, Oda and his prespectives. I always find the size to be accurate, it's just the perspective, it's just fucking weird. Like in one page where he managed to put the shichibukai lined up, where the closer one was on one side, and furthest away was on the opposite side. It's normal some sizes would feel screwd up, but they do make sense if you find the right perspective. This is the same. The giant could be further away than the rest. Or simply sitted down. But I do think he's a centaur. So a giant centaur would be... ... ... can't find adjective good enough.
Punk Hazard = Elbaf.
Newp. I don't think so. Too much hype for it to be replaced like this. But maybe they're doing studies with animals from elbaf. Including the Satyrs and the Centaurs. All these mythological beings in one place. It's not hard to see how one could call this "fablE"... But I just think Elbaf will be even better. With Valkyres welcoming people into the country of Valhala. (Island of Elbaf, or Vice-versa). And there will be unicorns and fairies and ... stuff.
So I'll go with "punk hazard has some of elbaf's fauna" while not refusing this theory totally. It's anti-climatic, but aside from that, it's a good theory!