The demon Nebiros was first mentioned by Johann Wier in 1583. He is supposedly the most valiant Marquis of Hell, has nineteen legions of demons under his command. He makes men cunning in all arts (and sciences, according to most authors), but especially in rhetoric, speaking with a hoarse voice. He also restores lost dignities and honors, although according to Johann Wier he procures the loss of them.
The 24th spirit of the Goetia, Naberius appears as a three-headed dog or a raven. He has a raucous voice but presents himself as eloquent and amiable. He teaches the art of gracious living. He is depicted as a crow or black crane.
Concerning his name, it is unclear if there is an association with the GreekCerberus. It is said that in 1583, Johann Weyer considers both of them to be the same demon. He claimed:
"Naberius [Naberus], alias Cerberus, is a valiant marquesse, shewing himselfe in the forme of a crowe, when he speaketh with a hoarse voice: he maketh a man amiable and cunning in all arts, and speciallie in rhetorike, he procureth the losse of prelacies and dignities: nineteene legions heare (and obeie) him."
The Grand Grimoire regards Nebiros as the Field Marshal and Inspector General of the armies of Hell. He can be conjured to inflict woes upon anyone, discover the Hand of Glory, teach the mystic and occult qualities of all animals, plants and minerals and supply necromantic advice. One of the three Goetic nobles under his direct authority is Naberius, suggesting that the Grand Grimoire's author understood the two spellings to signify distinct demons. The other two subordinates are Glasya-Labolas and Ayperos.
"Origin: Africa. The general of Hell. He oversees demons. He has knowledge of ores, plants, and animals, and can forsee the future. He is the most skilled soul controller in all of Hell."
—Shin Megami Tensei A-Mode DDS Dictionary
Nebiros appears as the Black Count, a demon who has imprisoned countless souls known as the Bodyconians in an attempt to create a false paradise for his and the Red Baron's adoptive daughter, Alice. Nebiros has imprisoned the girlfriend of the Law Hero as a Bodyconian, and when he attempts to rescue her, his soul is removed, killing him.
Nebiros can be found during the entrance test Flynn must pass at Tsukiji Hongwanji with his fellow Samurai. He can also evolve from Corpses once they reach level 39. Nebiros can teach Flynn the Mudoon, Pulinpa and Megidola skills through his Demon Whisper.
"The general of Hell. He keeps watch over other demons. One of hell's greatest necromancers, he can control souls and corpses."
—Shin Megami Tensei IV Apocalypse compendium
Nebiros appears in Shinjuku in the east entrance main street, Nicho, Kabuki-Cho passage, Kabuki-Cho and the Golden Gai areas. He can teach the Mudoon and Megido skills through his Demon Whisper. Nebiros benefits from learning Darkness and Almighty skills.
Devil Summoner: Raidou Kuzunoha vs. The Soulless ArmyEdit
Nebiros appears as a boss in the Dark Realm in Dark Kasumidai during Episode 5, after Raidou has collected all of Sadakichi's Report Pages. Nebiros is also required to unlock the hidden demon, Alice.
To do this, he must be at the party to answer the phone at Harumi-Cho after Belial has answered it in Tsukudo-Cho. Then, both must answer the phone at Ginza-Cho, summoning Alice and engaging her in battle. Following her defeat, both will imprison Alice's weakened form in a Staff of Death, asking Raidou to revive her through fusion.
"The general of Hell, he keeps watch over other demons. One of the greatest necromancers in Hell, he can control souls and corpses."
—Persona 3 compendium
Nebiros is a Persona of the Hermit Arcana. His fusion prerequisite requires that the protagonist be level 50 and have the Marionette key item. As the request that grants the Marionette isn't available until special fusions can be performed, Nebiros cannot be fused until after 9/21.
Nebiros appears in the Fifth Day at Kudanshita as an optional boss in the event Marquis of Hell. He claims to have appeared on behalf of his master, seeking "the human Bel." He will summon teams led by Badb Cathas, Abbadons and Mothmen, who will heal him when wounded and crowd around him, preventing enemy teams from reaching him. Once defeated, he leaves, acknowledging the party's power and commenting that his master will be pleased. He appears as a member of the Fiend Race in this game.
"The general of Hell. He keeps watch over other demons. One of the Hells greatest necromancers, he can control souls and corpses."
—Devil Survivor 2 compendium
Nebiros appears as a bonus boss on the 3rd Day, but must be unlocked for 30 points.
During the first battle with him, the protagonist needs to escort civilians out of the map, as he enters the field with three demon teams. However, as the player defeats those teams, Nebiros will use Necromancy to constantly revive them at full health (Necromancy resurrects up to all three) whenever his turn comes around.
Furthermore, if Nebiros is defeated while another demon team is present, he can simply reincarnate by taking over that team's body and reappearing at full health, now accompanied by two Pisacas. Thus, the player either has to mobilize all 4 teams to efficiently defeat him, or make use of the Kishins' Double Up/Matchless Racial Skills.
Defeating Nebiros causes him to retreat, earning the player the Nebiros Repeller title and unlocking the fight with Belial on the 5th Day.
During the fight with Alice, Nebiros appears alongside Belial. Like the previous fight, Nebiros will revive defeated demon teams and reincarnate himself if defeated while any loose team is present. He also has his Ice and Electricity affinities improved, along with being buffed to Level 91.
In spite of Nebiros' status in the demonic hierarchy and his mid-major role as a secret boss, he is not a unique demon, allowing the player to have multiple Nebiros demons on their team.