|Featured In|| Warbreaker|
”You cannot tempt the hearts of men who are pure, Nightblood.
Nightblood was created in a collaboration between Vasher and Shashara. A thousand Breaths were required, and a very difficult visualization needed to Awaken steel. Nightblood was Awakened with the command "Destroy Evil." The sword had no concept of evil, and so the Breaths it inherited decided "evil was someone who would try to take the sword and use it for evil purposes, selling it, manipulating and extorting others, that sort of thing."
The first hours of Nightblood’s life are imprinted into its memory, and it cannot overwrite its initial experiences and memories, such as Denth being fond of it and Shashara being alive. It is, however, very capable in some ways, able to grow and learn.
Vasher decided the knowledge of how to Awaken Type IV Entities was far too dangerous and killed Shashara to keep her from spreading it as she had done with the ability to make Lifeless from a single breath.
Powers and Characteristics
Nightblood is sentient but lacks a human context for its intelligence (sapience). Time has no meaning for it, nor can it well understand the dynamic aspect of human personalities. It can speak into Vasher's mind as well as Vivenna's, and it reads their surface thoughts whether they want it to or not. Though he thinks otherwise, Nightblood doesn't need to sleep. Nightblood can more easily influence and is better able to communicate with people who are mentally unhinged.
When its clasp is undone and even a bit of its blade shows, it leaks an inky smoke. The smoke is the Breaths that it has absorbed from its victims, twisted and fouled, leaking back out. Those it defines as "evil" feel drawn to possess it; once an "evil" person picks Nightblood up, the sword amplifies the wielder's bloodlust causing him or her to slaughter anyone nearby and then commit suicide with the blade. Even while still in its scabbard Nightblood is very powerful and enhances the person holding him, once Nightblood is unclasped every part of it is a deadly weapon that--literally--yearns to kill evil-doers, it can smash bones and even run a man through. Nightblood in effect "wields" the person holding the sword and always kills its holder by driving itself through their chest.
A "good" person, someone who wouldn't want to use Nightblood for evil purposes, feels sick while looking at Nightblood and touching it can induce vomiting. This sensation of nausea is suppressed if the user has drawn Nightblood and had his or her breath drained. Anyone who is able to wield Nightblood and survive, Bonds with the blade to a greater degree and is no longer repelled by or abnormally drawn to use it. 
Once drawn, Nightblood becomes incredibly powerful. Its voice becomes overpowering. Lifeless that it touches disappear in a puff of smoke and stone also disappears when struck. It is unknown what happens to a Living creature that is struck by Nightblood. So long as Nightblood is unsheathed, it drains the Breath from its wielder, drawing Breath faster the longer it is held until it is all gone. If held until all available Investiture (i.e. Breath) is consumed Nightblood will feed on the spark of life, killing the wielder. This will also happen to non-Returned that wield Nightblood. Nightblood can also feed on other forms of investiture, such as Stormlight.
Nightblood seemingly drew the color from a person who tried to wield it but was disarmed by Vasher before the sword could kill.
Nightblood is similar to a Shardblade (and is described as being something akin to a "robot spren"), but differs in that when the blade inflicts a wound, it vaporizes and destroys on all three realms, Cognitive, Physical, and Spiritual.. The similarity with Shardblades is intentional - Nightblood was created with knowledge of Shardblades.
Nightblood is completely black, both blade and hilt. The blade is thin, long, and straight, with cutting edges on both sides. The cross guard is referred to as being hooked. Its overall size is noted as large; most likely, Nightblood was made to fit the proportions of a Returned. It is sheathed in a silver color, all-metal sheath with a clasp on it to prevent easy release of Nightblood.
Based on Vasher and Vivenna's statements, Nightblood could be around 53 all the way to 60 inches long overall, with a blade of around 43-46 inches long.
Nightblood has no sense of gender assigned to itself. Vasher is responsible for originally assigning it male pronouns. It is fascinated by gender, and is still attempting to figure it out.
It is of note that Szeth makes no mention of any sensation of nausea or lust for Nightblood upon encountering it.
Assuming that Nightblood is not Allomantically inert, an attempt to burn it would be similar to an attempt to burn someone else's metalmind.
- Warbreaker chapter 21
- Annotation for Warbreaker chapter 35
- Annotation for Warbreaker chapter 54
- Does Nightblood need to sleep?
— 17th Shard forums - Oct 5th, 2013
- Annotation for Warbreaker chapter 53
- Annotation for Warbreaker chapter 51
- Annotation for Warbreaker chapter 55
- Does Nightblood rip souls out of bodies, by chance?
— Theoryland - Mar 4th, 2014
- Is everyone at risk of dying from wielding Nightblood unsheathed for too long?
— Theoryland - Apr 15th, 2013
- Now that Nightblood is on Roshar, can it feed off of Stormlight the same way it can off of Breaths?
— Theoryland - Jan 8th, 2015
- r/books AMA 2015 - He's closest to a spren, but kind of like a...robot spren
— Arcanum - 2015-07-25
- Would Nightblood also work like a shardblade, in that it severs the soul instead of consuming it when it touches a person?
— Reddit - May 18th, 2015
- There are those involved who knew that Shardblades existed before they tried the Nightblood experiment
— Reddit - Aug 2nd, 2015
- Warbreaker prologue
- Nightblood's blade is long and straight with edges on both sides
— Reddit - 10 June 2015
- Words of Radiance chapter 88
- Edgedancer chapter 16
- What is Nightblood's opinions on gender, and who decided on him having he/him pronouns?.
— Reddit - Mar 13th, 2015
- Firstly, you're assuming Nightblood is not allomantically inert (...) but if it was, it would be like trying to burn someone else's metalmind.
— 17th Shard forums - Nov 5th, 2015
|Characters||Vasher · Vivenna · Siri · Lightsong · Denth · Susebron · Llarimar · Bluefingers · Blushweaver · Nightblood|
|Places||Hallandren · T'Telir · Idris · Kuth · Huth · Tedradel · Court of Gods|
|Magic||Awakening · BioChromatic Breath · Command · Drab · Heightening· Ichor-alcohol · Lifeless · Returned|
|Mythology and Lore||Endowment · Austrism · Five Scholars · Iridescent Tones · Manywar · Kalad's Phantoms|