O
I had 2 theories on how Law's cutting abilities work
1.) is that he basically uses his fruit in tandem with his sword in a similar way haki is used on swords. If he can't cut something with his strength & swordsmanship then his ability won't work but if he can cut something with his physical stats/sword the ability keeps that thing alive. This would explain why Vergo was reluctant to dodge Laws attack, as he was confident Law wouldn't be able to cut through him.
2.) He can cut anything with his ability and the only way to avoid it is to dodge with CoO or block him from actually landing a sword slash (which is what DD did in this panel)
1.) is that he basically uses his fruit in tandem with his sword in a similar way haki is used on swords. If he can't cut something with his strength & swordsmanship then his ability won't work but if he can cut something with his physical stats/sword the ability keeps that thing alive. This would explain why Vergo was reluctant to dodge Laws attack, as he was confident Law wouldn't be able to cut through him.
2.) He can cut anything with his ability and the only way to avoid it is to dodge with CoO or block him from actually landing a sword slash (which is what DD did in this panel)
inconsistent.
