Trafalgar Law is a very tricky opponent to overcome in One Piece, given his keen intellect and creative abilities.
Known as the Surgeon of Death, Law is highly regarded for his technical prowess. He can manipulate anything within his range via the Ope Ope no Mi. In layman's terms, anybody under his sphere of influence becomes a patient at his operating table, making it one of the most versatile fruits in One Piece history.
With an impressive bounty of 500,000,000 berries, Law is a major threat to the World Government and could definitely give several One Piece characters the fight of their lives. It's not easy going up against Law, but it can be done by a select few. Only a fool would make the mistake of underestimating him.
Note: This article will contain major spoilers from the manga.
One Piece characters that Law can actually beat
4) Donquixote Doflamingo
During the Dressrosa saga, the Heavenly Yaksha (nickname of Donquixote Doflamingo) was almost taken out by Law's Gamma Knife technique. However, his powerful Ito Ito no Mi allowed him to stitch his organs back together. Law didn't have the physical strength or stamina to win this particular battle.
However, this changed by the time One Piece got to Wano Country. Law has become significantly more durable since he can now withstand direct punches from Big Mom herself. Readers have to remember that she is on the same level of Kaido, who could easily destroy Doflamingo.
Law also fully awakened his Devil Fruit, which means he can apply his techniques to objects rather than within a radius. A combination of K-ROOM and Shock Willie was enough to damage Big Mom herself and there is no way Doflamingo would survive an attack of this caliber.
3) Vinsmoke Sanji
Ever since the Onigashima Raid, Sanji has grown much stronger. After using the Raid Suit, he unlocked the genetic modifications of his body. Sanji now has an extremely durable exoskeleton with a healing factor and can also move faster than the eye can see.
Unfortunately for Sanji, Law can ignore his durability with the Gamma Knife. However, it won't be easy for Law as he will constantly have to dodge Sanji's attacks. With that said, he can alter his surroundings with his ROOM techniques. This would allow him to maintain his distance while distracting Sanji.
2) Roronoa Zoro
Zoro is a very tough swordsman who gave Kaido a permanent scar, via Nine Sword Style: Ashura. He also possesses the powerful Enma, which is classified as a Great Grade sword. Last but not least, he can also use the potent Conqueror's Haki.
Being a very close match for both fighters, Law would have to avoid getting hit by Zoro's named techniques in order to win. Once again, he would have to rely on his Devil Fruit for a major advantage. Gamma Knife can still bypass through Zoro's defenses without any trouble.
The swordsman does have tremendous pain tolerance, so he could likely survive this attack. However, Law could still finish him off with his Awakening techniques since these moves are strong enough to injure Big Mom.
1) Eustass Kid
The Jiki Jiki no Mi is a very dangerous fruit that allows Kid to manipulate magnetic force, allowing him to construct giant metal golems with high attacking power. He can even break the bones of Big Mom herself, which is a rare feat in the One Piece series.
Law could just as easily lose this match as he could win. However, he can use his Devil Fruit to cut through Kid's metal objects. Law is also a master strategist, whereas Kid just rushes into battle. The former could easily lay traps for the latter. Law simply has more tactical approaches than Kid does.
One Piece characters that Law can't beat at the moment
4) Monkey D. Luffy
The Straw Hat is simply too strong for anything less than the best. During the Onigashima Raid, he joined a select few One Piece characters who can infuse Conqueror's Haki into their attacks. Luffy can now evenly fight Kaido in physical terms, which few can ever do.
Law would certainly put up a good fight, but Luffy's Haki is far superior. Not many One Piece fighters can withstand the force of a Gear Fourth attack, with Conqueror's Haki only making it that much stronger.
3) Issho (Fujitora)
A good number of One Piece fans heavily downplay Fujitora, along with the other Navy Admirals in general. The powerful character only demonstrated a fraction of his power back in Dressrosa. The Zushi Zushi no Mi allows him to manipulate gravity itself and not many One Piece fighters can deal with such a strong ability.
Fujitora should be held in the same high regard as the likes of Aokiji and Kizaru. Back in the Fishman Island arc, it was directly stated that the Marines have only gotten stronger. It wouldn't make any sense for the new Admirals to be significantly weaker than the previous ones.
However, Law is not without a fighting chance here. He could use his Devil Fruit to cut down the meteors. However, Fujitora is also a highly perceptive swordsman, despite his blindness. His Observation Haki would allow him to see through Law's attacks and counter with his own sword techniques.
During Kaido's introduction to One Piece, he survived a 10,000 meter fall simply because "he was bored." The ending narration also had the following to say:
"People often say "If it's one-on-one, Kaidou will win." On land, sea, and air..."
Kaido is a brute force of nature with godly physical stats. During the Onigashima Raid, Law confirmed that he cannot move Kaido around due to his strong Haki. Kaido also managed to knock him out with his Raime Hakke, which forced Law to retreat even though he had backup from the other Supernovas.
Simply put, Law isn't going to last very long by himself.
1) Marshall D. Teach
Blackbeard is considered to be on the same level as Kaido and Big Mom, a very elusive tier among One Piece characters.
Keep in mind that Law and Kid had to work together just to fight Big Mom alone. Blackbeard is a much stronger threat, being the only character in One Piece who can use two Devil Fruits.
The Yami Yami no Mi would completely nullify Law's Devil Fruit powers, which immediately puts him at a severe disadvantage. Blackbeard could then crush Law with his earthquakes, courtesy of the Gura Gura no Mi.
Note: This article reflects the writer's personal views.