Shinigami Eyes

The eyes of a Death God can see human names and lifespan displayed above their heads. If a Death God drops his Death Note to earth and a human picks it up, they can grant that human the power of their eyes at the cost of the human's remaining lifespan being cut in half.

Humans who go through with the "eye deal" gain the ability to see other humans' names and lifespan, but cannot see their own lifespan or that of other Death Note users. They also gain 3.6 vision, as revealed by Ohba in How To Read 13. The eye deal is first referenced when Ryuk offers for Light to make the trade, only for Light to refuse as he is unwilling to give up half his lifespan.

In the manga, the Shinigami Eyes are depicted as being gold irises, with red pupils and pale yellow sclera, while in the anime, the irises are simply a bright red. In the films, they are depicted with a yellow 'cat eye' appearance, it should be noted that this is merely a representation of a person having the eyes, it is impossible (medically or otherwise) to notice who possesses the eyes.

In the novel Another Note, the antagonist Beyond Birthday (a former Wammy's student and would-be successor of L) is said to have been born with Shinigami Eyes, enabling him to see the names and lifespan of those around him. It is never explained how a human could be born with the eyes, though the idea of a Death God losing his eyeball and dropping it to Earth was mentioned.

Misa Amane briefly explains to Light that in order for the eyes to work, The person being looked at must be visually recognisable, the eyes will not work if the persons face is obscured or out of view, apparel (such as glasses) have no effect and do not prevent the name from being shown.

A persons name can be seen on video footage or by photograph, it is impossible to see the name on a drawing (however accurate), deceased persons names on photographs are not shown.

Misa Amane
Main article: Misa Amane

In all incarnations of the franchise, Misa Amane is the first character to be depicted as having gone through with the trade. After she is arrested on suspicion of being the Second Kira, Rem erases her memories of the Death Note, having refused to kill her and wanting the best for her. With her memories of the Death Note gone, Misa loses her Shinigami Eyes in the process. After regaining her memories and uncovering the buried Death Note that Light left in the woods, she makes a second eye deal with Ryuk, quartering her lifespan.

After the timeskip, Misa continues to use the power of the eyes up until Light orders her to forfeit her Death Note and pass it on to Teru Mikami, causing her to lose her memories and the Shinigami Eyes once more. It can be assumed that after Rem's death, Misa regained a portion of her lost lifespan, though the question of how much lifespan she had left remaining is moot, as How To Read 13 reveals she committed suicide a year after Light's death.

In the films however, she does not commit suicide and only loses her memories of the Death Note (and the eyes) after Light's death and L's burning of the notebooks. She is shown a year later, wondering why there seems to be a gap in her life.

Kyosuke Higuchi
In the manga and anime, Higuchi (as the Third Kira) gains the Shinigami Eyes after making the deal with Rem during his car chase. His time with the eyes is short-lived, as he winds up captured and dies shortly after, Light having written his name down on a scrap of Death Note.

Kiyomi Takada (film)
Main article: Kiyomi Takada

In the second film Death Note: The Last Name, the Yotsuba arc is removed, with Sakura TV and Kiyomi Takada serving in the respective places of the Yotsuba Group and Higuchi. Takada gains the Shinigami Eyes from Rem, but as in the case of Higuchi, winds up captured as Kira and killed by Light's scrap of Death Note.

Kal Snydar (A.K.A: Jack Neylon)
In the manga, after Sidoh discovers the mafia hideout, a subordinate of Mello known as Jack Neylon (real name Kal Snydar) is made to go through with the eye deal. In the first failed raid on the hideout, Jack reads out the names of the names of the special ops team as Sidoh unmasks each of the members, causing each man's name to be written down in the Death Note. Neylon/Snydar later dies during the second raid, as Light had written his name down in the Death Note, along with other mafia members' names. In the anime, the eye deal and the entirety of the first raid were left out.

Soichiro Yagami
Light's father winds up manipulated into gaining the eyes as part of Light's plan to infiltrate Mello's hideout the second time around, though Matsuda was the original intended target. With the power of the eyes, he is able to see Mello's true name (Mihael Keehl) but is shot up by one of the few remaining Mafia members and further wounded fatally by the explosion. Though Light tries to force the dying Soichiro to write down Mello's name in the Death Note, he succumbs to his wounds, relieved with believing that his son isn't Kira.

In the films, Soichiro never gets the eyes and doesn't die, as there is no timeskip or the events of "part 2". Unlike his manga/anime counterpart, he does learn that his son is Kira.

Teru Mikami
Main article: Teru Mikami

After gaining Misa's Death Note, Mikami is revealed to have made the deal with Ryuk in order to kill the members of Sakura TV's "Kira's Kingdom", one of them being Demegawa. He remains with "the eyes" up to his death.

Beyond Birthday
Main article: Beyond Birthday

Born with the eyes and killer of the BB murder cases

C-Kira
C-Kira ("Cheap Kira"), true identity unknown, is the catalyst of the post-series one-shot, where he/she kills off the elderly and sick, as well as people who wish to die. Though his/her identity is never revealed, he/she is depicted with Shinigami Eyes, presumably having made a lifespan trade with Meadra. C-Kira commits suicide at the end of one-shot after Near announces that he has no interest in the case (just like L, he will only work on cases he takes a personal interest in), having written his or her own name in the Death Note.