It is a common theme in anime for eyes to possess powers beyond anything imaginable. Some of the strongest characters harness their power within their eyes. There are eyes capable of mind-reading, creating illusions, and even destruction.

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Eye powers are usually both envied and feared by those who witness them. Along with these fearsome abilities, eye powers often bring an equally frightful appearance. Whether it's a weapon that has replaced the user's original eyes, a dark symbol representing a sinister power, or a change that manifests through the eyes' growing strength, the appearance of these eyes leaves a lasting impression on other characters and the audience.

10 King Bradley's Ultimate Eye gives him an intimidating appearance (Fullmetal Alchemist: Brotherhood)

wrath ultimate eye

The power of the Ultimate Eye gives King Bradley a huge advantage over his opponents in the series Fullmetal Alchemist: Brotherhood. It increases his perception to superhuman levels, allowing him to counter any attack with just a glance. This heightened vision makes any opponent powerless before him.

The ouroboros symbol is tattooed into his eye, replacing both his iris and pupil. This symbol gives his eye an unnatural and intimidating appearance, which he hides under an eyepatch. The scary look of the Ultimate Eye, coupled with its abilities, makes King Bradley a fearsome enemy.

9 Shinigami Eyes give the user an ominous & threatening stare (Death Note)

Death Note Misa Amane With Shinigami Eyes

In the series Death Note, humans in possession of a Death Note can bargain half of their life span to gain the ability to see the names and life spans of other humans. This ability is known as the Shinigami Eyes. These eyes look no different than any ordinary human's eyes. However, to the audience, they appear to be red with light-colored pupils. It is a very slight change but gives the user an inhuman and soulless look.

The eyes of the Shinigami who bestow a Death Note on a human appear even more disturbing as they ominously glow red while in use. Though the eyes of humans pale in comparison to the real thing, they're just as threatening. Given the price one must pay to obtain them and the characteristics that set them apart from normal eyes, the Shinigami Eyes are a very unsettling ability.

8 Ciel Phantomhive's Faustian Contract glows with a mysterious purple pentagram (Black Butler)

Black Butler Ciel Phantomhive Contract In Eye

At the start of Black Butler, Ciel Phantomhive unknowingly summons the demon Sebastian Michaelis. To take revenge on his captors, Ciel enters into a contract with Sebastian. He officially becomes his master at the price of his human soul.

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A binding seal inside Ciel's right eye represents the contract between the two. It displays a pentagram with the seal circling it and glows an eerie purple. The most disturbing aspect of Ciel's Faustian Contract is that it is made by a character so young. The seal on Ciel's eye represents the torture and pain he has gone through at such a young age.

7 Kurapika's Scarlet Eyes strike fear into those who catch their gaze (Hunter x Hunter)

Kurapika's scarlet eyes staring in Hunter x Hunter.

The Scarlet Eyes in Hunter x Hunter are some of the most famous and beautiful in the world. They are compared to the rarest jewels and are sought after by tradesmen and those in the upper class. The collecting and selling of these eyes wipe out almost the entire Kurta Clan, leaving only Kurapika remaining. The eyes glow a deep scarlet when the owner becomes angry or agitated. If the owner is to die in that state, the eyes remain scarlet permanently.

Those looking to profit off of this trait mercilessly hunt down members of the Kurta Clan. The appearance of the Scarlet Eyes can strike fear into those who catch their gaze, as is seen when Zenji confronts Kurapika only to be immobilized by his stare.

6 Kurumi Tokisaki's Clock Eye is a symbol of her deadly powers (Date A Live)

Date A Live Kurumi Tokisaki Eyes

Kurumi Tokisaki is considered the most dangerous spirit of the series Date A Live, due to her deadly abilities. Her left eye is a gold clock that gives her the power to manipulate time in her spirit form. These powers make her exceptionally dangerous, allowing her to take thousands of lives.

Her terrifying power aside, the creepiest aspect of her eye is how it contrasts with her otherwise cute appearance. The clock in her eye feels uncanny, the gold and red of her eyes bringing a sinister expression to her face. Her eyes are the centerpiece of her spirit form and give her look an unnerving and spooky feel when revealed.

5 Allen Walker's Cursed Eye has unpredictable power & dark symbolism in his scar (D.Gray-man)

D.Grayman Anime Allen Walker Cursed Eye

The Cursed Eye is a reverse pentacle scar given to Allen by Mana after his resurrection as an Akuma in the series D.Gray-man. It gives Allen the power to see the souls trapped within Akuma and appears as a large scar across his face. It first manifests as a black eye with red, glowing rings in place of his iris.

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As it increases in power, the symbol of a reverse pentagram replaces the red rings. The eye seems to have a will of its own and activates without Allen's control. It grows in power the more it is used and causes great pain to Allen. The unpredictability of its power and the dark symbolism of its appearance make the Cursed Eye a frightening ability.

4 The All-Seeing Eyes of God possess frightening power at a terrible price (Blood Blockade Battlefront)

Kekkei Sensen Leonardo All Seeing Eyes Of God

The All-Seeing Eyes of God in Blood Blockade Battlefront are artifacts bestowed onto chosen humans. In exchange for the sight of the person closest to them, they give the user many powers. These include heightened vision, illusion control, time perception, the ability to see and read auras, and the ability to control the vision of others. The artifact is put in place of the user's original eyes and glows a bright blue. Fine lines and circles detail the inside in replace of an iris and pupil. The All-Seeing Eyes of God permanently change the user.

Once removed, their eyes and sight will never be what they once were. They are a terrifying eye power, from their unnatural appearance to the harsh consequences of their use. Those chosen possess amazing abilities. However, the price of such power is very hefty.

3 Maximillion Pegasus' Millennium Eye requires a dire sacrifice in exchange for control of its power (Yu-Gi-Oh!)

Yu-Gi-Oh Anime Maximillion Pegasus Millennium Eye Reveal

In the Yu-Gi-Oh! franchise, the Millennium Eye is one of the seven treasures known as the Millennium Items. It grants the holder the power to see into the mind of an opponent. Pegasus uses this eye to keep a step ahead of his enemies at all times. His many victories are thanks to the power it contains. The Millennium Eye is a golden eye that replaces the user's original.

Pegasus had his own left eye removed so that he could wear the Millennium Eye. He conceals it behind his hair, keeping it secret from his opponents. The Millennium Eye is one of the more ominous of the Millennium Items, especially given the sacrifice necessary to take control of the artifact. It is a fitting power for one of Yu-Gi-Oh!'s first and most memorable villains.

2 The Rinne-Sharingan gives frightful, god-like powers to its user (Naruto)

Kaguya Otsutsuki Glaring in Naruto Shippuden

The Rinne-Sharingan is the most powerful of eye abilities in Naruto. It is a combination of Rinnegan and Sharingan, first achieved by Kaguya Otsutsuki after consuming the fruit of the God Tree. The Rinne-Sharingan appears as a third eye that forms in the middle of the user's forehead. It has the power to transcend dimensions, using genjutsu to transport the user and others to these dimensions at will.

The enormous power of the Rinne-Sharingan is more than a match for most Shinobi and techniques. Only the Rinnegan and chakra of the Tailed Beasts have successfully stopped its genjutsu. Giving those who wield it a frightful, inhuman appearance and godlike powers, the Rinne-Sharingan is without a doubt the most daunting of abilities in the Naruto universe.

1 The Kakugans of a Ghoul have a terrifying, demonic appearance (Tokyo Ghoul)

Tokyo Ghoul Anime Hinami Eyes Kakugans

In Tokyo Ghoul, the Kakugans of a Ghoul are a distinct characteristic and determining trait. Their appearance is a dead giveaway of a Ghoul's identity. They have black eyes with red irises and red veins that branch out from the eyes and into the skin. They can appear at the will of the Ghoul but also appear on their own when a Ghoul is hungry or excited. In some Ghouls, only one Kakugan activates.

Human-Ghoul hybrids also only develop one Kakugan that sets them apart from the typical Ghouls. Though they pose no known danger themselves, Kakugans give a terrifying, demonic appearance to Ghouls. They, along with the nature of Ghouls in general, strike fear into humans and captivate the audience with their starved gaze.

NEXT: Boruto: 10 Powers Sasuke Still Has After Losing His Rinnegan