4 darkest One Piece arcs (& 4 that are the most lighthearted)

Eiichiro Oda's record-breaking One Piece story stands out for its unique blend of humor and epicness, creating a narrative that overturns the conventional pirate trope. Monkey D. Luffy and his comrades don't seek treasure for greed; rather, their quest around the world is a cheerful adventure in pursuit of ultimate freedom.

Many One Piece characters' flamboyant antics and exaggerated behaviors fuel countless running gags as Oda injects his trademark humor even into the tensest situation. While these comedy moments have become integral to the manga's success, Oda's story often transcends mere comedy to delve into darker themes.

One Piece frequently shifts its usual humorous tone to confront impactful topics like brutality, racism, and slavery, offering a realistic and poignant depiction of the darkest sides of human nature. The stark contrast between moments of joyful comedy and harrowing scenes of profound darkness creates a compelling balance through One Piece's narrative, as some arcs are steeped in darkness, while others are more fun-oriented.

Four One Piece arcs that have a dark tone

1) Wano Arc

Yasuie's execution in the One Piece anime (Image via Toei Animation)

Before Luffy and his friends and allies liberated the country, Wano languished under the tyranny of Kaido of the Beasts Pirates and the shogun Kurozumi Orochi. Their oppressive rule caused the citizens of Wano and the country to endure terrible sufferings, setting a backdrop of desolation for the entire arc.

Kaido and Orochi established several weapon factories, resulting in large-scale pollution that reduced a large part of Wano to a wasteland. They also enslaved the residents, who were forced to work but deprived of any proper nourishment.

Left to starve, people were faced with heart-wrenching decisions, such as parents deciding to kill their children rather than let them continue to suffer from the unbearable famine.

Another shocking display of cruelty was Oden's death, with the samurai being boiled alive and then killed in cold blood by Kaido. The fate of many citizens was worse, as Orochi tricked the starving residents into eating some failed SMILE Devil Fruits that are known to induce forced happiness.

With that, Orochi robbed people of their freedom to express pain and sorrow for their misery. The SMILEs forced the Wano residents to laugh even in the most gruesome moments, such as Shimotsuki Yasuie's barbaric execution.

2) Dressrosa Arc

Law after the genocide, as seen in the One Piece anime (Image via Toei Animation)

Donquixote Doflamingo masked his cruel dominion over Dressrosa under a bright facade. The Straw Hat crew's arrival in the country exposed his misdeeds, such as enslaving dwarves in his SMILE factory and turning people into toys, thereby erasing their existence in the minds of their dear ones.

Doflamingo's sadistic wickedness is shown when he usurps King Riku's throne and torments his family. Yet, the narrative unveils even more unsettling truths as it delves into the backstories of Doflamingo himself and Trafalgar Law. It was revealed that Doflamingo experienced abuse himself when commoners tortured him and his family for their Celestial Dragon heritage.

This ordeal scarred Doflamingo to the point where he decided to kill his father, seeing him as responsible for this disaster in cold blood. His father, Donquixote Homing, smiled one last time, and the very next moment, Doflamingo shot him in the back of his head.

Doflamingo then brought Homing's head to Mary Geoise to regain the status of Celestial Dragon. However, that is not the darkest point of the Dressrosa Arc. Trafalgar Law's flashback showed how the World Government and Flevance's royal family let citizens die from Amber Lead poisoning to not stop the profit.

The disease was caused by prolonged exposure to Amber Lead. Falsely believing it to be contagious, the neighboring countries decided to kill all of Flevance's inhabitants to nullify any risk of contamination. Countless innocent people were slain, including Law's parents and little sister. Law, who was just a child, escaped death by hiding under a pile of corpses, leaving behind a disturbing image.

3) Sabaody Archipelago Arc

Sabaody's slave auction in the One Piece anime (Image via Toei Animation)

Despite its seemingly light-hearted tone, with Duval's gag and the Sabaody Amusement Park, the Sabaody Archipelago Arc focused on dark themes such as human trafficking, slavery, and racism. It was revealed that the Celestial Dragons were privileged nobles who could do whatever they wanted, including enslaving others to own them as their property.

The enslaved people were marked with a symbol that was meant to indicate that they were inferior to normal humans and to allow the Marines to hunt them down should they try to escape. They were also forced to wear a collar set to explode if its chain was broken. The Celestial Dragons could trade, torture, and kill the enslaved people they please.

Sabaody painted a disturbing picture of humans being bought and sold like items in an auction house and forced to walk around with collars like dogs. The racism toward Fish-Man race members was also shown as Hatchan, Camie, and Pappag had to hide themselves out of fear of being recognized and captured.

The slave auction left the Straw Hats disgusted, but their darkest hour was yet to come. Shortly after, Luffy and the others suffered a devastating defeat at the hands of Admiral Kizaru. This disaster led to the Straw Hat crew's unprecedented separation, which may look like a minor event in today's eyes, but it was profoundly shocking at the time.

4) Egghead Arc

One Piece epitomizes the banality of evil in Kuma's flashback (Image via Toei Animation)

The adventure set in Dr Vegapunk's futuristic island pushed One Piece into realms of darkness akin to those in seinen series. As Jewelry Bonney delved into Bartholomew Kuma's memories, he unveiled how the Celestial Dragons had enslaved Kuma and his parents, and the corrupt system of the nobles was exposed like never before.

Kuma's mother died of starvation, and his father, a good man named Clapp, was shot dead by his owner for making too much noise while trying to cheer up his son. Kuma, who at the time was a child, had to endure relentless abuse from the nobles, but nothing could compare to the horror of being splattered with the blood of his father, brutally killed in front of him.

The Celestial Dragons crushed Kuma's tender family, but their evilness didn't stop there. It was revealed that the nobles used to perpetrate genocides just for fun, as they indulged in disconcerting games where the participants received different points for each human target they killed. With zero consideration for human life, the Celestial Dragons planned to kill 100,000 people in God Valley.

Despite being just a boy, Kuma was among the "targets" of the manhunt. Within this hellhole, Kuma befriended two kids, Ivankov and Ginny. The three children managed to survive the inferno, and Kuma went to live with Ginny in Sorbet, with the two growing up together.

At one point, however, Ginny was abducted by a Celestial Dragon, forced into marriage, and later released when she fell ill. Kuma saw Ginny again only when he found her corpse. Beside her was a one-year child, the evident byproduct of the coerced wedlock with the noble who had kidnapped her.

This was likely One Piece's most disturbing storyline, depersonalizing the once joyful Ginny into an expendable object. The fact that the Egghead Arc concluded with Saint Saturn's gruesome death at the hands of Imu-sama only cemented this arc as the darkest in One Piece.

Four more One Piece arcs that are lighthearted and fun

1) Return to Sabaody Arc

The fake Straw Hat Pirates in the One Piece anime (Image via Toei Animation)

After two years of intense training in preparation for the New World, the Straw Hats reunited on Sabaody, where they were scattered by Bartholomew Kuma two years earlier. This reunion starts a brief arc, highlighted by the surreal idea of a group of imposters who tried to impersonate the Straw Hats to capitalize on their reputation for their ends.

The attempt was laughably bad. The imposters had completely different faces and body shapes than the original Straw Hats, making the disguises grotesque. The funniest thing is that the objectively preposterous ruse managed to fool many people, including some seasoned pirates who went to pledge their loyalty to the alleged Straw Hats.

After the high-stakes drama of Sabaody, Impel Down, and Marineford, this arc was a much-needed comedic intermission, underlined by many ludicrous gags such as Sanji's reaction to Perona, the "contest" of the order of arrival at Shakky's bar, and, of course, the fake Straw Hats trying to recruit Chopper by enticing him with a cucumber. That's not even mentioning how Chopper could not tell the fake Straw Hat Pirates apart from his comrades.

2) Thriller Bark Arc

One Piece's zombies were funny, not scary (Image via Toei Animation)

Despite its eerie setting, the Thriller Bark Arc is characterized by an inherent light-hearted vibe, playing with mainstream horror tropes to make fun of them. The exaggerated, cartoonish portrayals of most of the arc's antagonists, starting with Gecko Moria, elicited laughter rather than fear, especially compared to other villains like Crocodile, Rob Lucci, or Doflamingo.

Characters like Perona, Hogback, and Absalom were meant to be dangerous villains, but their hilarious antics made them more entertaining than menacing. Likewise, the zombies were nowhere as terrifying as they should have been, appearing as a parody of horror movies. They only generated comic relief that complemented Usopp, Nami, and Chopper's over-the-top reactions.

Except for the intense confrontation with Kuma, the arc was a non-stop comedy fest. Brook's jokes, Franky's random moments of surreal carpentry, the fight between Sanji and Absalom, Usopp's hilarious immunity to Perona's depression-inducing ghosts, and the Straw Hat crew's absurd docking system were just some of the countless gags.

The scene where a zombie pops out from the ground only for Luffy to nonchalantly push it back into the ground as if it were the most natural thing to do was another iconic gag that set the arc's playful tone together with the equally memorable "Zombie Night" dance sequence.

3) Skypiea Arc

Skypiea showed the funniest Zoro in the whole One Piece series (Image via Toei Animation)

The Skypiea Arc was filled with epic moments, like Wyper's heroic resistance against Enel and Luffy's triumphant ringing of the Shandorian Golden Bell. Nevertheless, the Straw Hat crew's trip to Skypiea carries the vibe of a light-hearted vacation rather than a high-stakes expedition, at least compared to other arcs.

This relaxed, vacation-like atmosphere was manifested by a never-ending series of gags. Luffy's "Idiot Song" is impossible to forget, and the same goes for his absurd impressions or the moment when he mistook a skeleton for Nami. Even Roronoa Zoro, known for his unyielding stoicism, became a source of comedy in Skypiea.

Fans couldn't help but laugh at the thought of Zoro's hilarious confrontation with the South Bird, and the green-haired swordsman's Tarzan-like moment was just as amusing. Usopp's antics and the presence of a comic relief character like Gedatsu further epitomized the arc's humorous essence.

4) Long Ring Long Land Arc

Luffy vs Foxy was One Piece's peak comedy (Image via Toei Animation)

The Long Ring Long Land Arc deviated from the typical pattern of the Straw Hat Pirates saving an oppressed country to delight fans with an entertaining, low-stakes interlude between major tense events. Eccentric characters like Tonjit and, of course, Foxy and his subordinates defined the playful tone of what could easily be considered to be the funniest arcs.

The whimsical confrontation between Straw Hat Pirates and Foxy Pirates in the bizarre pirate game Davy Back Fight encapsulated this arc's spirit. Silliness reigned supreme as the game was blatantly rigged, setting the stage for comedy that reached its peak with the appearance of Luffy's surreal Afro transformation and the subsequent grotesque clash between Luffy and Foxy.