Great chapter.
In terms of the fight, imo there are a few possibilities,
1) Vergo basically underestimated Law's ability/strength and was overpowered by his ability. He was probably like i will charge at him and beat him and won't (need to) dodge his attack. He paid the price by getting cut. If this is the case, then maybe if he didn't underestimate law the fight would have been longer and the winner unknown.
2) Maybe Vergo isn't/wasn't all that. I think in previous chapter discussion other also mentioned this too. Most trusted doesn't have to mean strongest.
3) Law is currently very strong ( back to 1 kinda). Vergo is still at the top in terms of strength but Law is just much stronger. If that's the case i wouldn't be surprised if the current Law was stronger than Luffy at this time at least. I don't think Luffy can use Haki defense on spot ( or on his whole body) defensively ( or at least in an efficient way) yet. At least based on the fishmen Island thus far.
4) Law's ability is just one of those broken one. If you get hit by it you are basically done for until it's undone or maybe other ways to revert back i don't know. In this scenario Luffy ( or others) maybe could still dodge the abilities. Something like Vergo vs Smoker fight. Law got the heart and it was that, but it took him a while to do that. Most likely Smoker was dodging/defending against it. but i guess Luffy could do the same since he is super fast. So in this case we wouldn't really know who is stronger law or luffy
Lastly, Could vergo also have an ability to revert back? Or maybe there are ways you can revert back abilities *_*. Although i do agree that the fight is probably finished, i am still having my fingers crossed until next chapter.
P.S. When you have a One piece chapter thread having more posts than a Naruto one, you know the chapter was just that great haha
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