Nightblood (Warbreaker)

"Hello! Would you like to destroy some evil today?"

- Nightblood's initial greeting to Szeth

Summary
Nightblood is a powerful, sentient sword created by Shashara and Vasher through the process of  Awakening. It was created as a replica of the Shardblades from Roshar that they saw upon Worldhopping, and was made to be used in the Manywar. Vasher used it in order to kill Shashara, and after such changed its name to Nightblood.

After the war ended Vasher continued to carry the blade with him, and it began to grow and develop more than any Awakened object should be able to, at least according to his own understanding of it. This lasted for centuries, with him still holding onto the blade in Nalthian year 327. Over this period it took in an immense amount of Investiture over time and became the most Invested non-Shard object or entity in the Cosmere.

It has been to other worlds sometime before it's later arrival at Roshar.

During some time after Vasher fled to Roshar, at some time a few generations after the Pahn Khal Rebellion, and before the Rosharan year 1163, they became separated and it came into the hands of the Nightwatcher at some point before Dalinar went to her in 1168, and eventually passed into the hands of Nale sometime after 1168, who gave it to  Szeth after bringing him back from the dead on Ishishach 1173 (1173.10.10.3). During some point before coming into the hands of Szeth, it passed through Lasting Integrity.

In early Jeses 1174, it was brought through Yeddaw, a city in Tashikk. It was here that Lift first saw it.

It was of great use during the Battle of Thaylen Field in Nanabah 1174 (1174.2.7.5), used in order to slay the Thunderclasts which were beyond the capacity of normal Shardblades to defeat.

It attracted great curiosity from Taravangian due to what its existence implied for the Diagram, leading to them interviewing previous bearers upon what exactly it is and how it works.

It has its Spiritual and Cognitive Aspects taken and used by Taravangian to kill Rayse in Vevishah 1175 (1175.4.10.5)

Appearance
Nightblood is completely black, both blade and hilt. The blade is thin, long, and straight, with cutting edges on both sides. Its crossguard is described as hooked, and it has a pommel at the end of its hilt.

It has an aluminium scabbard described as looking like silver, with a clasp in order to prevent it from being drawn.

It is likely between around fifty-three all the way to sixty inches (135 cm - 152 cm) long overall, with a blade length somewhere between forty-three to forty-six inches.

When drawn, it emits a twisted, black smoke, which is fouled Investiture that it had taken in, bubbling up and leaking out.

Personality
Nightblood is sentient but lacks a human context for its intelligence. Time has no meaning for it, nor can it understand the dynamic aspect of human personalities. The first hours of its life are imprinted into its memory, and it cannot overwrite the initial experiences, such as Denth being fond of it and Shashara being alive. It is, however, very capable in some ways, able to grow and learn.

It is usually cheerful, eager to help, and craves approval, but it is very self-centered and it does not like to be ignored. It often tries to convince people to draw it, and is often bored or frustrated when sheathed.

As an Awakened object, Nightblood's goal is to fulfill its Command, "Destroy evil", and sees this as its central purpose. Even though, due to the lack of human context for its intelligence, lacks the ability to accurately discern what is and isn't evil. Although they actively think of themselves as not being evil, and actively defends themselves when others consider them as such.

They have an extremely bad sense of time, to the extent of thinking of an event that happened centuries ago has having happened yesterday.

He is notably very friendly towards everyone, and would even be friendly towards Hoid, a man that most people who have interacted with him despise.

He has a particular distrust of priests.

Shashara
He cares for Shashara, though he has difficulty wrapping his mind around the idea that she is dead.

Vasher
Vasher has difficulty accepting the sword's ability to grow and change, often thinking himself crazy when he notices changes and developments. It's hard for him to regard the sword without bias. He still talks to Nightblood expecting an answer, though there hasn’t been an answer in years.

Powers and Stats
Name: Nightblood, Sword-Nimi, Unknown original name

Origin: Warbreaker

Age: At least 400 (It was at least 327 by the events of Warbreaker, and still exists during the True Desolation, which takes place "a few generations" after the Pahn Khal Rebellion)

Gender: Genderless, usually referred to as Male , considered Female by Lift

Classification: Sword, Type IV BioChromatic Entity, "Third Generation Shardblade"

Wielders: Shashara, Vasher, Nale, Szeth, Lift (Briefly), Taravangian (Briefly)

Powers and Abilities: Durability Negation, Soul Manipulation, Empathic Manipulation (It is capable of tempting others, and can induce in those that hold it a sense of intense bloodlust), Immortality (It is able to live on for hundreds of years, and it does not have biological limitations that make it able to age and perish), Inorganic Physiology (It is completely inorganic, being made entirely of steel), Telepathy (It is capable of talking into the minds of those around it), Self-Sustenance (As a non-living being, it does not need to eat, drink, or sleep in order to function), Statistics Amplification (It greatly enhances the strength of the wielder, to a superhuman extent. Even allowing a guard to stab himself through the chest with the blade, when it was still in its scabbard), Pain Manipulation (The wielder feels extreme pain in the arm or arms holding Nightblood), Resistance to Magic (Due to being very highly Invested, it is very resistant to all Invested Arts, and is basically immune to any use of them)

Attack Potency: His ability to dissolve objects and destroy their Cognitive and Spiritual Aspects is immense, he was capable of dissolving a ten foot wide circle of stone; destroy a Thunderclast, which are easily five or six times larger than a person; chipping a Honorblade; and even being capable of destroying the Vessel of a Shard, that being of Rayse, by striking at his Cognitive and Spiritual Aspects.

Speed: As a weapon, he cannot move by himself, and has his speed limited by the speed that his wielder can swing him.

Intelligence: He has a very hard time understanding human emotions, and cannot truly tell apart from good and evil with any emotional intelligence or understanding of nuance. He also has a very limited ability to learn and change, and has his initial knowledge and experience imprinted on his mind, and cannot learn the truth if it contradicts with that. Such as not understanding that Shashara is dead and that Vasher and Denth are no longer friends. Complex chains of logic confuse them. He can learn, but is very, very slow at learning. Along with this, while drawn, their mind goes fuzzy as their Command takes over, leaving them bordering on mindless.

Weaknesses:

Nightblood
Nightblood is an incredibly powerful blade created by him and Shashara through the use of Awakening, in an attempt to replicate the powerful Shardblades found on Roshar.

Holding it greatly enhances the strength of the user, and one simply need to slightly unclasp it to get the increase in strength. Enough so that Szeth could easily break the spine of a man by smashing him in the back, and a prison guard on Nalthis could run it through his own chest while still sheathed.

If anything is so much as nicked by the blade, they would burst into black smoke and have all of their Investiture absorbed. This brings about destruction in all Three Realms. It was powerful enough that it was capable of killing Rayse, a Shard of Adonalsium ; collapsing a Perpendicularity, and putting a nick in an Honorblade. As Souls are essentially of Investiture, this can also permanently kill Fused by consuming their Soul beyond its ability to resurrect.

As it is so oversaturated with Investiture, it leaks it out as black smoke, corrupted and fouled by the blade. It is this which got the sword its name. It consumes even the Investiture of the wielder itself, and if it consumes all they have, it would absorb their soul and spark of life. This absorbing of Investiture causes the wielder great pain, even before their soul gets absorbed into it.

Along with this, it causes colours to deepen around it when drawn.

Empathic Manipulation
He is capable of greatly effecting the minds of those that hold him if he deems them as "evil". He draws them to him, and when they wield him, he greatly amplifies their bloodlust causing them to kill everyone around them and then commit suicide.

A "good" person, someone who wouldn't want to use Nightblood for evil purposes, feels sick while looking at Nightblood; touching it can induce vomiting.

The issue in this, is that Nightblood does not have the ability to properly determine what is evil and what isn't. This is due to it not having human context for its understanding of reality, largely due to being made from an object which lacked any moral reasoning.

Telepathy
It is capable of communicating with the minds of those around it, able to project its voice into their mind, and read their surface level thoughts whether they want it to or not. It is also capable of projecting images into peoples minds.