Monkey D. Luffy has overcome enemies that once seemed impossible to defeat. From defeating powerful Warlords to taking down an Emperor of the Sea, every major battle has pushed him closer to becoming the Pirate King. His awakening of Gear 5 and the power of the Sun God Nika placed him among the strongest fighters in One Piece, proving he can stand alongside the world’s elite.
Even so, Luffy has never been portrayed as an unstoppable hero who wins every battle on his own. Many of his greatest victories came with help from the Straw Hat Pirates, allies, or enemies who had already been weakened before the showdown. That has always been one of One Piece’s biggest strengths. Success is usually earned through teamwork, determination, and perfect timing rather than overwhelming power alone.
As the Final Saga continues, the series is introducing opponents whose abilities and experience still put them above Luffy’s current level. Some are legendary pirates who shaped the Great Pirate Era, while others are mysterious figures whose full strength has yet to be revealed. These characters continue to fuel debates among fans, with many agreeing that even Gear 5 would not guarantee Luffy a solo victory.
This list looks at 18 One Piece characters that Luffy still cannot defeat without help, based on what the manga has shown so far.
1. Imu Remains the Biggest Unknown Threat in One Piece
Imu is one of the most mysterious characters in One Piece, and that mystery is exactly why many fans believe Luffy still has no chance of defeating them alone. Unlike the Yonko, Admirals, or other powerful fighters, Imu does not need public displays of strength to establish authority. Instead, Imu secretly rules the World Government from the Empty Throne, while even the Five Elders follow every command without question. That alone suggests Imu stands above the world’s strongest political and military powers.
The biggest clue about Imu’s true strength came during the destruction of the Lulusia Kingdom. In a single attack, an entire nation disappeared from the map, showing a level of destructive power far beyond anything Luffy has faced so far. Although the exact source of that attack has not been fully explained, it proved that Imu possesses resources and influence capable of wiping out entire civilizations.
Another important detail is that Luffy has never directly confronted Imu. The story has deliberately kept them apart, making it clear that this meeting is being saved for the final stages of the series. While Gear 5 has greatly increased Luffy’s abilities, nothing in the manga suggests he is currently prepared to overcome someone who stands at the very top of the world’s power structure.
2. Shanks Still Sets the Standard for Haki Mastery
Shanks has always been one of the strongest pirates in One Piece, even though he has never relied on a Devil Fruit. His reputation comes almost entirely from his incredible Haki, making him one of the few characters who can dominate battles through pure skill and overwhelming spiritual power. This is one of the biggest reasons many fans believe Luffy still cannot defeat his former idol in a one-on-one fight.
Throughout the series, Shanks has repeatedly demonstrated why he is feared across the Grand Line. His arrival at Marineford was enough to end the Summit War without another major battle, as both pirates and Marines respected his strength. More recently, his clash with Eustass Kid showed just how overwhelming his Haki has become. Shanks defeated Kid and his crew almost instantly, proving he remains one of the most dangerous fighters in the world.
Luffy has made tremendous progress with all three forms of Haki, especially after mastering Advanced Conqueror’s Haki during the Wano Arc. Combined with Gear 5, he has reached the Yonko level and defeated Kaido. However, becoming stronger does not automatically mean surpassing someone who has spent decades perfecting Haki alone.
Shanks represents experience, precision, and complete control rather than flashy transformations. His fighting style relies on making every attack count, something Luffy is still learning as the Final Saga continues.
3. Big Mom Was Never Defeated by Luffy
Charlotte Linlin, better known as Big Mom, remains one of the strongest pirates in One Piece despite her defeat during the Wano Arc. While she was eventually removed from the battlefield, it is important to remember that Luffy was not the one who defeated her. Instead, Trafalgar Law and Eustass Kid worked together, combining their awakened Devil Fruit abilities to force her underground before the massive explosion beneath Wano finally removed her from the fight.
Even before Wano, Big Mom consistently demonstrated incredible durability. She could withstand powerful attacks with little visible damage, and her immense physical strength allowed her to overwhelm many experienced fighters. Her Soul-Soul Fruit also gives her abilities that few other characters possess. By creating Homies like Prometheus, Napoleon, and Hera, she can attack from multiple directions while continuing to pressure opponents in close combat.
Although Gear 5 gives Luffy far greater freedom in battle than he had during earlier arcs, defeating Big Mom alone would still be an enormous challenge. Her stamina, durability, and decades of combat experience make her one of the toughest opponents in the series. She has repeatedly shown the ability to continue fighting after taking attacks that would defeat most other pirates.
Until Luffy proves he can defeat someone with Big Mom’s endurance without outside assistance, she remains one of the few former Yonko who could still push him beyond his current limits.
4. Saint Jaygarcia Saturn’s Regeneration Makes Him Extremely Difficult to Defeat
Saint Jaygarcia Saturn quickly established himself as one of the most dangerous members of the Five Elders during the Egghead Arc. Unlike many powerful enemies, Saturn does not rely only on overwhelming attacks. His greatest advantage is his incredible ability to recover from damage that would normally end a fight.
Luffy has already shown that Gear 5 gives him enough power to knock Saturn back and dominate several direct exchanges. In terms of physical strength, Luffy clearly can compete. The real problem begins after those attacks connect. Saturn repeatedly regenerates from serious injuries, making it extremely difficult for Luffy to make lasting progress.
This changes the entire nature of the battle. Luffy usually defeats opponents by wearing them down over time with constant pressure and increasingly powerful attacks. Against Saturn, that strategy becomes much less effective because the damage disappears. Even if Luffy lands several devastating blows, Saturn can recover and continue fighting almost immediately.
Another challenge is that the full source of Saturn’s regeneration has not yet been explained. Without understanding how his powers work, finding a permanent way to defeat him becomes far more complicated than simply hitting harder.
The Egghead Arc suggests that defeating the Five Elders may require more than overwhelming strength. Their mysterious abilities appear to follow different rules than most Devil Fruit users, making them unique threats for the Final Saga.
Based on what the manga has shown so far, Luffy has the strength to challenge Saturn, but defeating him without help or discovering the secret behind his regeneration still appears highly unlikely.
5. Blackbeard Is Still One of Luffy’s Biggest Obstacles
Marshall D. Teach, better known as Blackbeard, is one of the most dangerous pirates in One Piece because no one truly knows how strong he can become. Unlike every other known Devil Fruit user, Blackbeard possesses the powers of two Devil Fruits. His Dark-Dark Fruit allows him to absorb attacks, create powerful darkness, and even cancel the abilities of other Devil Fruit users through direct contact.
Blackbeard has also built one of the strongest pirate crews in the New World. Many of his commanders possess dangerous abilities, making him an even greater threat during large-scale battles. However, even without his crew, Blackbeard has repeatedly shown that he can defeat powerful opponents through his own strength and clever planning. His victories over major pirates have steadily increased his influence, eventually earning him the title of Yonko.
Luffy has never fought Blackbeard in a true one-on-one battle, so there is no clear evidence that Gear 5 would be enough to defeat him. While Luffy has grown tremendously since the Paramount War, Blackbeard has continued to become stronger during that same period.
6. Kizaru’s Speed Is Still a Serious Challenge for Gear 5 Luffy
Admiral Kizaru has always been one of the fastest characters in One Piece. Thanks to the Glint-Glint Fruit, he can move and attack at the speed of light, making him incredibly difficult to track in battle. His speed is not his only strength, though. Kizaru can also create powerful laser attacks, launch devastating kicks, and attack from long distances without giving his opponents much time to react.
The Egghead Arc finally gave fans a proper fight between Luffy and Kizaru. Although Gear 5 allowed Luffy to keep up with the Admiral, the battle also showed just how exhausting that transformation can be. Luffy needed his strongest form simply to compete, while Kizaru continued forcing him to chase an opponent who rarely stayed in one place for long.
Another important detail is that Kizaru was not completely focused on defeating Luffy. His mission involved carrying out the World Government’s orders rather than engaging in a prolonged duel. Even so, he repeatedly demonstrated that his speed alone could create major problems for the future Pirate King.
A rematch under different circumstances could produce a different result, but the manga has not yet shown Luffy clearly surpassing Kizaru. Gear 5 gives Luffy incredible freedom and creativity, yet speed remains one of the hardest abilities to counter.
7. Dracule Mihawk Is a Level of Swordsmanship Luffy Is Not Built to Counter
Dracule Mihawk has held the title of the World’s Strongest Swordsman for years, making him one of the most respected fighters in One Piece. His incredible skill with the black blade Yoru allows him to defeat elite swordsmen with remarkable precision. Even before the story entered the Final Saga, Mihawk had already established a reputation powerful enough to earn the respect of pirates, Marines, and the World Government alike.
Unlike many characters on this list, Mihawk is not someone Luffy is expected to fight. The series has consistently presented him as Zoro’s ultimate goal rather than Luffy’s final opponent. Zoro’s dream has always been to surpass Mihawk and claim the title of the world’s greatest swordsman. That long-running storyline makes a serious battle between Luffy and Mihawk highly unlikely.
Even so, comparing their current abilities remains interesting. Luffy relies on powerful Haki, creative Devil Fruit techniques, and close-range combat. Mihawk specializes in precision, reach, and devastating sword attacks that can cut across enormous distances. His fighting style is completely different from the opponents Luffy usually faces.
There is also very little information about Mihawk’s full strength because he has rarely been forced into an all-out battle. That mystery makes it difficult to measure his true limits.
8. Silvers Rayleigh Still Has the Experience Luffy Has Not Reached
Silvers Rayleigh played a major role in Luffy’s journey by training him during the two-year timeskip. Under Rayleigh’s guidance, Luffy learned the basics of Observation, Armament, and Conqueror’s Haki, giving him the foundation needed to survive in the New World.
Even in his old age, Rayleigh has repeatedly demonstrated incredible combat ability. During the Sabaody Archipelago Arc, he successfully held off Admiral Kizaru, showing that he remained capable of competing with one of the Marines’ strongest fighters. Years later, he also intimidated powerful enemies through his reputation and Haki alone.
Luffy has improved dramatically since completing his training, especially after unlocking Advanced Conqueror’s Haki and Gear 5. However, Rayleigh possesses decades of real combat experience that cannot be replaced through power alone. His understanding of Haki remains among the best in the series, and he knows how to use it with remarkable efficiency.
A serious fight between a teacher and student is unlikely to happen because of their close relationship.
9. Garp Is Still Powerful Enough to Push Luffy Beyond His Limits
Monkey D. Garp may officially hold the rank of Vice Admiral, but his achievements place him among the greatest fighters in One Piece history. Long before the current generation of pirates set sail, Garp fought legendary figures such as Gol D. Roger and played a key role in defeating the Rocks Pirates. His reputation was earned through raw strength and incredible Haki rather than a Devil Fruit ability.
Recent chapters have shown that Garp remains an extraordinary fighter despite his age. During the Hachinosu conflict, he displayed devastating Advanced Conqueror’s Haki attacks capable of destroying large sections of the battlefield with a single punch. His speed and physical strength continue to rival many younger fighters, proving that he is still one of the Marines’ greatest assets.
Although age has naturally reduced some of his stamina, Garp remains far from weak. His experience, battle instincts, and overwhelming Haki allow him to compete with opponents who would defeat most other veterans.
Luffy has reached Yonko level and continues to grow stronger with Gear 5, but surpassing his grandfather is another challenge entirely. Garp possesses decades of combat experience against the strongest pirates in history, giving him an advantage that goes beyond physical strength alone.
10. Sengoku’s Experience Still Gives Him the Edge Over Gear 5 Luffy
Sengoku may no longer serve on the front lines, but that does not change what he accomplished during his years as Fleet Admiral of the Marines. Throughout the era of Gol D. Roger and Whitebeard, Sengoku earned a reputation as one of the strongest Marines in history. His Mythical Zoan Human-Human Fruit, Model: Buddha, grants him incredible physical power and destructive shockwaves, while his mastery of Haki makes him a dangerous opponent even without relying on his Devil Fruit.
The Summit War also highlighted Sengoku’s authority and combat ability. He stood alongside legendary figures such as Garp and the Admirals while leading the Marines during one of the biggest battles in the series. His reputation was built over decades of fighting some of the world’s strongest pirates, giving him an experience advantage that very few characters can match.
Luffy has grown tremendously since the timeskip and reached Yonko status after defeating Kaido. However, Sengoku represents an older generation that survived countless battles against legendary opponents. His knowledge of combat, leadership, and Haki gives him tools that cannot be measured through strength alone.
11. Monkey D. Dragon Has Not Revealed His True Strength Yet
Monkey D. Dragon is one of the biggest mysteries in One Piece. Despite being the leader of the Revolutionary Army and the World’s Most Wanted Man, the manga has revealed very little about his actual fighting abilities. This lack of information has only increased speculation about how powerful he truly is.
Dragon commands an organization that openly opposes the World Government, something no ordinary fighter could accomplish. His influence reaches countries across the world, and even the highest-ranking officials treat him as one of their greatest enemies. That level of respect suggests Dragon possesses both exceptional leadership and incredible personal strength.
Several scenes have hinted that Dragon may have weather-related abilities, but Eiichiro Oda has never officially confirmed whether these powers come from a Devil Fruit or another source. Because of this, fans still know very little about how Dragon fights or what his full abilities look like in battle.
Luffy has become one of the strongest pirates alive, but there is no evidence that he has surpassed his father. In fact, the story continues to keep Dragon’s true power hidden, which usually signals that an important reveal is still coming.
12. Kuzan Continues to Be One of the Strongest Fighters in the New World
Kuzan, formerly known as Admiral Aokiji, remains one of the most powerful characters in One Piece. Even after leaving the Marines, his strength has never been questioned. His Ice-Ice Fruit allows him to freeze entire oceans, create massive weapons from ice, and control the battlefield with remarkable precision.
Before leaving the Marines, Kuzan fought Sakazuki in a ten-day battle that permanently changed the climate of Punk Hazard. Although he lost that fight, surviving such an intense battle proved that he belonged among the strongest fighters of his generation.
Since joining the Blackbeard Pirates, Kuzan has become even more unpredictable. While his true motives remain unclear, his decision to work alongside one of the world’s most dangerous Yonko has placed him at the center of the Final Saga. Recent chapters have also shown that his physical strength and Haki remain exceptional, thanks in part to his training under Garp.
Luffy has never faced Kuzan in a serious one-on-one battle. Although Gear 5 gives Luffy incredible freedom during combat, Kuzan’s experience, powerful Devil Fruit, and high-level Haki make him a difficult opponent for anyone.
13. Marco the Phoenix Is Still One of the Hardest Fighters to Put Down
Marco may not receive as much attention as the Yonko or Admirals, but he remains one of the strongest pirates in the world. As the former First Division Commander of the Whitebeard Pirates, Marco spent years protecting one of the greatest crews in history while fighting alongside legendary pirates.
His Mythical Zoan Phoenix Fruit gives him one of the best defensive abilities in One Piece. Marco can regenerate from injuries that would defeat almost anyone else, allowing him to continue fighting even after taking heavy damage. This unique healing ability makes long battles especially difficult for his opponents.
During the Marineford War and the Wano Arc, Marco repeatedly demonstrated why he is respected across the seas. He successfully fought powerful enemies, protected his allies, and held off multiple top-tier opponents despite being heavily outnumbered.
Luffy has become much stronger since those events, especially after awakening Gear 5. However, defeating Marco would require more than landing stronger attacks. His regeneration allows him to recover from damage repeatedly, forcing opponents to find another way to win.
14. Gol D. Roger Is Still the Standard Every Pirate Must Chase
Gol D. Roger may no longer be alive, but he remains the greatest benchmark in One Piece. As the only pirate known to conquer the Grand Line and reach Laugh Tale, Roger became the first Pirate King and inspired an entirely new era of piracy. His legacy continues to influence every major event in the series.
Roger achieved everything without relying on a Devil Fruit, instead mastering Haki to an extraordinary level. He fought legendary opponents such as Whitebeard on equal terms and played a major role in defeating the Rocks Pirates alongside Garp. His achievements established a standard that very few characters have ever approached.
Luffy has inherited Roger’s dream and many of his ideals, but the manga has never suggested that he has already reached Roger’s level. Becoming a Yonko and awakening Gear 5 are major accomplishments, yet the journey to becoming Pirate King is still unfinished.
Roger’s importance goes beyond strength alone. He represents the ultimate goal that every pirate hopes to surpass. Until Luffy discovers the One Piece, reaches Laugh Tale, and proves himself against the strongest remaining opponents, comparisons with Roger will continue.
15. Whitebeard’s Peak Strength Is Still Beyond Luffy’s Current Level
Edward Newgate, better known as Whitebeard, earned the title of the World’s Strongest Man for a reason. During his prime, he possessed incredible physical strength, unmatched endurance, and one of the most destructive Devil Fruits ever introduced. His Quake-Quake Fruit could create massive earthquakes capable of shaking entire islands and even threatening the seas themselves.
The Marineford War showed just how powerful Whitebeard remained despite old age, illness, and serious injuries. Even after suffering countless wounds, he continued fighting against the Marines while protecting his crew. His determination and overwhelming power left a lasting impression on both allies and enemies.
Luffy met Whitebeard during the Summit War, but the two never fought. At that point, Luffy was far too inexperienced to challenge someone of Whitebeard’s caliber. Even today, Gear 5 Luffy has not demonstrated enough to clearly surpass Whitebeard at his absolute peak.
Many fans continue to rank prime Whitebeard among the strongest characters in One Piece history. His combination of Haki, physical power, and destructive Devil Fruit abilities created a level of strength that remains difficult to match.
16. Rocks D. Xebec Was a Monster Even Roger Could Not Defeat Alone
Rocks D. Xebec is one of the most mysterious figures in One Piece, but the little information revealed about him speaks volumes. He commanded the legendary Rocks Pirates, a crew that included future legends such as Whitebeard, Kaido, Big Mom, and Shiki. Leading so many powerful individuals at the same time already shows how extraordinary Rocks must have been.
The God Valley Incident provides the biggest clue about his strength. During that battle, Gol D. Roger and Monkey D. Garp joined forces to defeat the Rocks Pirates. The fact that two of the greatest fighters in history had to work together has led many fans to believe Rocks was among the strongest characters the world has ever seen.
Although Eiichiro Oda has not yet shown Rocks fighting on screen, his reputation continues to grow with every new revelation. His influence shaped the pirate world long before the current generation began their journeys.
Luffy has made incredible progress throughout the series, but there is nothing in the manga that suggests he has reached the level of a figure who required both Roger and Garp to stop.
| Started | October 22, 1997 |
|---|---|
| Publisher | Shueisha |
| Author | Eiichiro Oda |
