We don't know for a fact how Luffy's future sight would work against someone without it, but if it's anything like how Katakuri's worked against Luffy at the start, then Luffy would be almost impossible to hit, even without the Mochi fruit's logia-like properties.
Another issue is Luffy's armament. Sanji was just injuring himself when kicking Vergo's presumably tekkai+haki defense with his level of armament. And Vergo doesn't event have a great level of armament haki, since Law had to overpower Vergo's haki for his fruit to chop Vergo in half, and Law isn't really known for notably powerful armament. I think it's safe to assume that something similar could happen with Luffy's newly improved armament, seeing just how much it improved.
In the end, Sanji would probably have a hard time even landing a hit on Luffy and when he does it would only deal neglectible damage, especially when you remember just how tanky Luffy is. On the flip side, even though future sight is mostly a defensive skill it would still give Luffy an edge in attacking and his improved armament would deal immense damage to Sanji.
Especially in recent months, Luffy’s growth throughout One Piece’s New World saga has been nothing short of astronomical. Going from taking out Warlords to giving Kaido a genuine one-versus-one fight is truly breathtaking progress for One Piece’s future Pirate King protagonist.
Despite his astronomical growth, there are still some challenges which Luffy can’t yet quite overcome. Likewise, when considering Luffy’s growth as of late, there are some characters who will simply never have a hope of defeating him.
Here are five One Piece characters who could still defeat Luffy, and five more who never will.
Warning: One Piece anime spoilers below.
Roger and four other One Piece characters who are still above Luffy’s level
1) Blackbeard
With the power of both the Dark-Dark and Tremor-Tremor Fruits, Blackbeard is most likely still above Luffy’s level. While many theorize that Luffy’s Awakening will be specifically tailored to defeating Blackbeard, this has yet to happen in One Piece and thus is still speculative.
Even with Advanced Conqueror’s Haki, it’s likely Luffy doesn’t yet have the tools needed to defeat Blackbeard in a fight.
2) Whitebeard
Although Whitebeard is unfortunately dead in contemporary One Piece, it’s still a safe assumption Luffy wouldn’t have been able to beat Whitebeard. While Kaido is called the “The Strongest Creature,” Whitebeard was known as “The Strongest Man in the World” during his time alive.
Even if Kaido were stronger, the Whitebeard’s mastery of the Tremor-Tremor Fruit, combined with Luffy not having an Awakening, spells the latter's victory.
3) Gol D. Roger
Likewise, although dead, Roger was still no doubt above Luffy’s level in terms of strength. Especially through anime-only scenes during the Oden flashback (which are different from filler), the strength of both Roger and his crew are seen in all their glory.
Roger and his men, as seen during the Oden flashback, would simply be too strong for Luffy to defeat in a fight.
4) Kaido
While their fight is still going on and Luffy will likely end up being the winner, he still lost to Kaido several times prior. With the two being shown as going completely back-and-forth in their fight when last seen, it’s likely that the two are relatively even in strength.
Kaido obviously has the necessary tools to defeat Luffy, so there’s no reason to believe he can’t .
5) Shanks
While Shanks’ combat skills are seen very sparingly throughout One Piece, there’s little to no doubt he’s stronger than Luffy and could defeat the Supernova. As Luffy’s role model, it wouldn’t make sense to have him be stronger than Shanks at this point in the story.
Furthermore, Shanks’ clashing with both Whitebeard and Kaido in pre-time-skip One Piece establishes him as at least on their levels, if not higher.
Sanji and four other One Piece characters who will likely never defeat Luffy
1) Koby
Much like how Garp never definitively got a true win over Roger, it’s likely Koby will never be able to definitively claim victory over Luffy. While Koby does have Admiral-level aspirations within the Marines, he’s still likely going to fall short of Luffy in combat.
Were Koby to eat a Devil Fruit, his chances may be better, but for literary device’s sake, he’d likely still lose to Luffy each time.
2) Buggy
Arguably the most beloved comic relief character in One Piece, it’s likely Buggy will always fall short to Shanks’ protege. In their first encounter, Luffy was able to get the best of Buggy, and while the two haven’t been at odds since, the result will likely be the same.
Buggy has also seemingly made little to no combat improvements since the Marineford arc, whereas Luffy has grown by leaps and bounds since then.
3) Sanji
Although Sanji technically does have a win over Luffy when he wasn’t defending himself, it’s unlikely that outcome would be repeated in a real fight. Sanji has yet to awaken his Conqueror’s Haki (if he even has it), while Luffy and Zoro are awakening and honing their Advanced Conqueror’s Haki.
Until Sanji can prove his own strength more or awaken his own Conqueror’s Haki, it’s unlikely the Straw Hat Chef will ever defeat Straw Hat himself.
4) Jinbe
While Jinbe is no doubt an incredibly impressive fighter in One Piece, he’s still not quite on Luffy’s level. Being paired up against and defeating Who’s Who in Wano is no doubt an impressive feat, but nowhere near the level of going up against Kaido.
5) King
Even with his impressive Lunarian genetics and resistance, King likely wouldn’t last long against Luffy in a one-on-one fight. Like Zoro, Luffy also recently awakened his Advanced Conqueror’s Haki, which proved to be the main component in Zoro’s victory over King.
Additionally, the speed of Luffy’s attacks would be a perfect match against King, who offers quick moments of vulnerability when his flames are down. While King's speed also goes up in these moments, it’s doubtful that Luffy wouldn’t be able to handle it with his Snakeman and Gear Second form.
Edited by Sijo Samuel Paul
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