Showing Eddie Brock visions of the past, Knull reveals that he came into being in the abyss that existed before the beginning of the universe, content to slumber in the endless darkness of the Void. When the Big Bang occurred, the Celestials appeared and began flooding the abyss with cosmic light, creating planets and seeding them with life; awakening Knull, who was outraged by this pollution of his kingdom of darkness. When a Celestial picked him up to examine him, Knull bared his fangs, plunged his hand into his newly-cast shadow, and pulled out a sword of living darkness — the first symbiote. Decapitating the Celestial with a single strike, he attempted to attack the others but was repelled and cast back into the abyss. Converting the Celestial's severed head into a forge, Knull used its divine energy to refine the crude blade - revealing that the symbiotes' vulnerability to intense heat and sound is a psychosomatic condition passed down through their genetic memory of this forging.
Manifesting a suit of armor from the same eldritch darkness as his sword, Knull embarked on a genocide against the gods; his symbiotic weapon becoming known as All-Black the Necrosword. While massacring a group of gold-armored gods, Knull was stabbed through the face while simultaniously impaling the last one through the heart. Crash-landing on a desolate planet, Knull awakened to find that All-Black had been stolen by one of the planet's indigenous inhabitants - who would unwittingly go on to continue Knull's deicidal crusade.