Sliver of the Eye

The Sliver of the Eye is an artifact of the Void given to Billie Lurk by the Outsider after she rescues Daud from the Eyeless Gang. A fragment from an ancient Void entity, it enables Billie to see things that were hidden to her before, such as hollows, and enables her to use Foresight and Displace.

Death of the Outsider
When Billie arrives at Shindaerey North Quarry and uses Foresight, she can detect the direction of the Void entity, which burns her eye. It is revealed that the Sliver is a part of the Eye of the entity. By touching the Eye, the Eye blackens and Billie gains the ability to see the part of the Void that overlaps with the physical world. This eventually helps her find the Ritual Hold, where the body of the Outsider is held.

The Veiled Terror
After the Outsider was severed from the Void, the Sliver started to burn almost constantly, causing intense pain to Billie. It has also lost both Foresight and Displace abilities, but instead allows Billie to detect any supernatural object and phenomenon by painting them with red, blue, yellow auras, or a combination of the three colors. In addition, the Sliver is also drawn to the Void, thus physically pulling Billie toward any void rift. The Sliver also allows Billie to see inside Void rifts, which would have been impossible with normal eyes.

Trivia

 * During The Veiled Terror, Billie wore an eye patch over the Sliver to avoid unwanted attention.
 * To help with the pain, Billie started to chew a type of addictive herb called Green Lady, which eases the pain by dulling the mind. The herb has a variant called Black Weed of Karnaca, and is also known as Fool's Fancy in eastern Morley.
 * The ability that allows Billie to see Hollows is called Glimpse Hollows, according to the Dishonored Roleplaying Game.