One Piece is often mistaken for a lighthearted series that only has humorous characters. But it couldn't be further from the truth. The series tackles many serious issues that viewers may face at some point in their lives. One Piece also consists of some terrifying characters.
Most of these characters have a vicious personality that is accompanied by a scary design. The amalgamation of the two things is enough to strike fear into the hearts of the audience, but some characters take things up a notch with their abilities. By using the darkest abilities at their disposal, they manage to increase their notoriety further.
7 Soru Soru no Mi
The Soru Soru no Mi belongs to Big Mom, the queen of Totto Land and one of the Four Emperors. She used to be a member of the Rocks Pirates before eventually starting her own crew. Big Mom is unhinged, and there is no way to tell when she could kill someone. She has killed her own children for the most trivial things.
There is no easy way to stop Big Mom, especially when she is angry. Whenever someone infuriates her, Big Mom uses the power of the Soru Soru no Mi to steal their entire lifespan. With such a dark ability, it is no wonder that even her kids fear her.
6 Yami Yami no Mi
The Yami Yami no Mi literally translates to the Dark Dark Fruit. It was eaten by Blackbeard after he stole it from Thatch. He had been waiting to get his hands on the Devil Fruit for a very long time, and it is easy to see why. It allows Blackbeard to manipulate darkness at will, making it the darkest ability in One Piece.
The darkness created by the Devil Fruit is unique, and it has a strong gravitational force that crushes everything inside. It is also able to nullify the abilities of other Devil Fruit powers, which is probably the main reason why Blackbeard wanted it in the first place. Blackbeard can also use the Yami Yami no Mi to absorb the attacks of his enemies.
5 Shibo Shibo no Mi
The Shibo Shibo no Mi is a Paramecia-type Devil Fruit that was eaten by Charlotte Smoothie. It was introduced in the Whole Cake Island arc, where Smoothie used its power to extract juice from various things, both living and non-living.
This is a scary ability, as it drains the moisture from an individual's body and leaves them in a dehydrated state. When Smoothie used it on a woman, all she could do was scream and plead for her life. Needless to say, it is a dangerous power, and fans may get an opportunity to see it again in the future.
4 Hobi Hobi no Mi
The Hobi Hobi no Mi was eaten by Sugar of the Donquixote Pirates. After consuming the Devil Fruit, Sugar stopped aging physically, which would have been a serious side effect if not for its absurd power. The Hobi Hobi no Mi is a terrifying Devil Fruit. With its aid, Sugar is able to turn any individual into a toy.
A person affected by the Devil Fruit's ability becomes a sentient toy. While they do remember everything, their existence is removed from the minds of those who know them. It is frightening to even think that a person is bound to a toy's body with no one even trying to acknowledge their existence.
3 Ice Oni Virus
The Ice Oni virus was created by Queen. Prior to becoming a pirate, he used to be a member of MADS, a legendary scientific group led by Dr. Vegapunk. Queen learned a lot about Lineage Factor and various other things. He used this information to create new weapons, which he added to his arsenal.
One of his most impressive creations is the Ice Oni virus. It spreads from one person to another rapidly, and there is no way to get rid of the virus except by consuming the antidote. The people infected by the virus see a spike in their physical abilities, but they also start losing their sanity. Eventually, the strain placed on their bodies causes them to lose their senses completely and ultimately die. It is indubitably one of the darkest powers in the series.
2 Kage Kage no Mi
Gecko Moria's Kage Kage no Mi has a fearsome ability that allows him to steal the shadows of other people. Moria used its power to create an army of undying zombies, which would help him achieve his goals.
Once Moria manages to steal the shadow of a person, they end up in a two-day coma. Furthermore, they are forced to remain in the shadows, as the slightest exposure to sunlight can vaporize them instantly. Given its nature, it is no wonder why Moria was able to fight against the likes of Kaido.
1 Mori Mori no Mi
The Mori Mori no Mi is a Logia-type Devil Fruit that is in the possession of Admiral Ryokugyu. The power of the Devil Fruit was demonstrated toward the end of the Wano Country arc. Ryokugyu can use the Mori Mori no Mi to create and control plant life.
The plants created by Ryokugyu are extremely durable and can easily overwhelm multiple opponents. The roots can enter the body of an opponent and drain moisture from their body, leaving them completely incapacitated. This particular ability makes it extremely difficult to fight Ryokugyu.