@Alpha:
Wanted to throw this in there, can we really trust Law? We saw how he ran off from Dofla and must have "used" him and his organization in some way or another. I mean from what we know, he is the ONLY pirate that has a Subamarine, now how useful is that? Maybe he took some technological plans from Dofla and had someone build it for him, we'll never know! I swear he must have ate the Ope Ope no mi and the Weasel Weasel no mi! I hope he doesn't use Luffy and co down the road, I know I know he said "I'm not sure anymore who's using who anymore" but still.
He definitely is using the Straw Hats, but after his discussion with Smoker last chapter, I don't really think it matters. Luffy is a force of nature, and none of Law's carefully laid out plans are going to matter when throwing Luffy and the Straw Hats into the mix.
D.D's face finally had a change in color due to his anger as stated by Buffalo and he's completely loosing his care free demeanor. In addition to all of this, we finally get a power scale here with the fact that D.D is absolutely afraid of Kaidou and his crew, he's sweating and shouting. I just wanted to add here that all those who think X Drake wanted to take on Kaido on his own are completely out of line, if Kaido's name makes a veteran like D.D get an upset stomach then I can't imagine how X Drake could stand up to him.
To be fair, if Luffy wasn't the protagonist of the series, do you honestly think you would consider Luffy capable of taking down not just one, but all of the Yonko? From a glance, X. Drake's power seems more formidable than Luffy's. We all know that's not true, of course, but it stands to reason that X. Drake had/has a lot going for him. He has an Ancient Zoan, specifically one that transforms him into a T-Rex, he was a Rear Admiral for the Navy, and he is, currently, a Supernova. Now, it's likely that Kaido still has his number because of his army, his Haki, and likely, his Mythical Zoan Devil Fruit, but it's conceivably possible that X. Drake thought he stood a chance. Nevertheless, I expect we'll be seeing X. Drake sooner rather than later, and that he will play some role in the downfall of Kaido.
Say what you will, I still think Shanks is the strongest Yonko around regardless of what the Manga has to say, his power and crew are just as a mystery as Kaido and his crew.
Out of Kaido, Big Mom, and himself, yeah, I agree. If we throw Blackbeard into the mix, though, it's fairly obvious that BB takes the crown. Shank's scar and BB's prophetic words to him at Marineford are proof enough of that.