"I was...unrefined in those early days. And as such, the creation of the proto-symbiote was...unclean. To this day, the weaker of my creations carry the scars of their progenitor's birth inside of them. They still fear the fire of the forge...and the discordant and incessant noise of a Celestial hammer beating their will into something...wieldy. Into something...beautiful. My weapon forged, I set out to banish the bright and all that came with it. In time, my living blade would become known as All-Black. The Necrosword. The Godslayer." -Knull god of all-Symbiotes-

All-Black is an immensely powerful Necrosword forged by Knull at the dawn of time using his firstborn symbiote and the cosmic energies from a dead Celestial's head. Taken from its dark creator, the Necrosword was notably wielded by Gorr the God Butcher for a time to slay gods.

Secretly, the Necrosword was linked to and empowered by the Celestial that was used to forge it, who created an afterlife that absorbed the souls of all slain by the Necrosword. That link is now severed.

At the dawn of the Seventh Cosmos, Knull was found by the Celestials and was recruited as the King in Black. However, he created the first symbiote from his shadow, shaped into a sword, and used it to behead one of the Celestials. For this, Knull was banished by the other Celestials, but within the slain Celestial's head, the primordial symbiote was tempered using the Celestial's divine power.

A Necrosword made from living darkness, All-Black was wielded by Knull during the dark god's deicidal rampage, earning it the moniker of the Godslayer. All-Black was metaphysically tethered to the decapitated Celestial's undead corpse, which was trapped in the Realm Between and became a grotesque afterlife imprisoning the souls of those slain by the Necrosword.

After Knull was incapacitated during a battle against a group of golden-armored gods, All-Black left him and bonded to a misotheistic alien called Gorr, who unwittingly followed in Knull's footsteps, used it to slay gods across the cosmos, and earned the title of the God Butcher. Feeding off the slain gods' blood, All-Black corrupted Gorr into a kind of evil god himself, bestowing him with immortality and a host of other abilities resembling those Knull had possessed. As a result of Knull and Gorr's deicidal campaigns, All-Black became the subject of countless stories and legends containing grains of the truth, with its history being recorded in a divine tome called the Saga of the God Butcher. After being beaten by mortal followers of Thor, Gorr discovered he could use All-Black's living abyss to create semi-sentient creatures called Black Berserkers, which he used to assist him in his killing spree.

All-Black is sentient and possesses a malevolent will of its own, though it was subservient to its creator Knull and seeks to carry out his agenda of purging all life from the universe, especially the gods. Like other symbiotes, it is capable of communicating with its hosts and seeks to corrupt them; being indicated to have influenced the already misotheistic Gorr into becoming the deicidal God-Butcher,trying to influence All-Father Thor into killing Old Galactus, and corrupting Old Galactus into the monstrous Butcher of Worlds.

The first and most-powerful symbiote manifested by Knull from the living abyss, All-Black is metaphysically tethered to the undead corpse of the Celestial used to refine it, which supplies it with power in exchange for assimilating the souls of those slain by the Necrosword. In addition to the abilities bestowed by lesser symbiotes, All-Black grants its host powers similar to those of Knull himself. As a result, Gorr -- a mere mortal -- was able to kill countless gods and essentially became a dark god himself, able to simultaneously defeat three versions of Thor. It is also able to fire blasts of dark energy, to augment the wielder's own divine abilities, and kill immortal beings as powerful as the Celestials, Galactus, and Ego.

Superhuman Strength: All-Black augments its host's strength to the extent that a mortal such as Gorr was able throw chunks of a moon into space; best Young Thor, present-day Thor, and All-Father Thor in combat all at the same time; and single-handedly defeat millions of gods in open combat, including one that supposedly "wrestled with black holes for fun." However, it is meant to be wielded by a god: Knull was able to decapitate a Celestial with a single strike, King Thor was able to defeat Galactus in single combat, Galactus effortlessly destroyed countless planets using its power, Ego used it to devour the last of the Celestials of Earth-14412, and Loki effortlessly destroyed Ego as a test of his newfound power.

Superhuman Durability: While wielding All-Black, Knull was able to survive prolonged combat against armies of hundreds of other gods; while Gorr able to survive a massive lightning bolt summoned by Thor, the Godblast of an Odin-Force powered All-Father Thor - which propelled him "several light years" away in a matter of seconds - and survived being immersed in a star to no ill effect. When thrown into a black hole in an attempt to destroy it, All-Black was unharmed and eventually assimilated the singularity. Loki was also engulfed in Ego's magma while destroying him to no ill effect.

Superhuman Speed: By manifesting wings, All-Black enables its host to fly at hypersonic and possibly faster-than-light speeds, as when Gorr quickly overtook Thor during their first encounter.

Superhuman Reflexes: Gorr was able to catch Thor rather easily off guard, as well as many other gods.

Longevity: After bonding to All-Black, Gorr lived for at least three-thousand years and still looked to be in his prime.

Regeneration: While bonded to All-Black, Gorr was able to recover from a lightning strike within four days with no signs of injury from the incident. He was also able to regenerate or reattach his arm after it was severed by Thor.

Constituent-Matter Manipulation: While All-Black's original and preferred form is that of a sword, it is able to shapeshift to create clothes, armor, wings, weapons, and tendrils from its living abyss. It can also be used to create semi/fully sentient entities as minions, such as the shadowy beasts known as the "Black Berserkers".

Dark Energy Manipulation: All-Black is capable of wreathing itself in or discharging blasts of purple energy -- as seen during Knull's battle with the Silver Surfer, and when Gorr used it to blow up a Space Shark in his battle with young Thor. It was also capable of augmenting the innate energy projection abilities of its hosts, as seen when All-Father Thor used it to strengthen both his Thorforce and mystical lightning when battling Galactus, turning them black.

Chain-Breaker: When wielded by Dylan Brock, the Necrosword catalyzes his transformation into his King in Black form, Codex, and can be used to channel his ability to sever symbiotes from the Hive-Mind. When this ability is used against a King in Black, due to being severed from the Hive-Mind, they lost their powers. However, prolonged use of the Codex transformation causes Dylan pain due to his half-human body being unable to handle the Necrosword's power.

Metaphysical Connection to the Headless Celestial: Connected to Headless Celestial through Knull's use of its severed head as a forge, the Headless Celestial supplies the primordial symbiote and its host with a vast amount of power, making even mortal hosts like Gorr nigh-invincible. The Celestial created an afterlife within itself and it absorbed the souls of whomever was slain by the Necrosword; thus, the more the Necrosword killed, the more powerful it became. This connection was ultimately severed by the Valkyries, greatly weakening the Necrosword.

Knull notes that All-Black's forging gave it and most subsequent symbiotes a psychosomatic fear of intense heat and sonic vibrations. Despite this, All-Black was not only able to survive being thrown into a star to no ill effect but turn it black - causing an assortment of ill omens in the process.

Hello! here with you, your friend MassterGolden900 and I bring you one of the most powerful weapons "or swords" in the Marvel universe or Marvel comics. (or it was before more legendary gadgets arrived that would overshadow Knull's sword) as we already know, Knull forged this weapon. and this sword is capable of damaging anyone. I don't know if it would be a competitor for other swords, like the Fierce Deity, Blade of Olympus, Eden Sword, but this one? It's the one I like the most. Anyway! with you the famous Necrosword or also called All-Black The Necrosword! Cause disasters with the sword of the god of the symbiotes. Bring darkness to San Andreas with the help of this beautiful bloody sword. (let's be honest, more than made of Symbiotes it looks like blood)

By the way, if you're wondering why I sometimes take so long to upload stuff? It's because I'm finishing up a couple of simple mods. But that's it, I need someone experienced in creating cleo mods. (Anyone who wants to help me? Send me a message and give them my Discord username.)