Vulcan was a Roman God of fire, forge, metalworking, and volcanoes. He is one of Mr. Wednesday’s oldest allies. He has created a comfortable life for himself by harnessing his powers for the modern world, which makes him resistant to Wednesday’s plans. Vulcan does not appear in the novel.
As the god of weaponry and fire, Vulcan has done well for himself in America's gun-obsessed culture. He is known to the old gods as the "god of volcanoes". Vulcan was bitter for being forgotten and unworshipped, but then he learned to "franchise" his faith by receiving an upgrade from the new gods and becoming the god of firearms. He made a bullet factory in his name wtih those who fired the bullets "praying" in his name. In order to further sustain himself, human sacrifices are made by having employees at his factory fall into his smelter.
In Virginia, the company town of Vulcan ammo is starting its morning. The supervisor greets employees as they go about their jobs. He heads upstairs to a catwalk over vats of molten metal. He leans against a railing that gives way and sends him plummeting into one of the vats, dissolving him into bullets. Shadow and Wednesday arrive to deserted streets. Shadow spots several white townspeople dressed in uniforms with red armbands and carting around rifles. They come across the funeral parade where the rest of the townspeople are marching behind Vulcan. Wednesday explains how a couple of people a year die in sacrifice at the factory because it's cheaper for the company to settle than to update the safety of the plant.
The crowd gathers in front of Vulcan as he gives a speech. Wednesday parks the car and gets out with a bottle of Soma to convince Vulcan to join him in his war. Vulcan finishes his speech and the crowd shoots their guns and rifles up into the air, causing Shadow to flinch. Vulcan tells the crowd to go in peace and Wednesday suggests for Shadow to take cover. Shadow gets back into the car as it starts raining bullets down, denting Betty yet falling harmlessly around Vulcan and Wednesday. After the bullets stop falling, Shadow joins Wednesday and Vulcan, confirming what Vulcan heard about Wednesday's plans to start a war. Vulcan offers to get them something to eat.
Shadow stares at a noose hanging from a tree as Vulcan tells him it was an "old hanging tree." Shadow turns around and when he turns back, the noose is gone. Vulcan offers for them to stay as long as they like while Betty is getting fixed up but Shadow wants to leave. Instead, they head inside Vulcan's house, gratuitously littered with preserved animal carcasses and rifle racks. Vulcan pours a drink for himself and Wednesday, outright denying Shadow anything to drink. He discusses how sacrifices have built up his mini empire and suggests Wednesday could have the same by sacrificing himself as he had done before. Shadows looks uneasily out the window at the hanging tree as Vulcan asks him if he has ever seen anyone hanged before and that it's a terrible way to find faith. Vulcan has "franchised" his worship and he pulls out a gun as he explains that the people believe and worship him through firepower. He aims and shoots at a mounted deer head. Wednesday invites him to join them in Wisconsin but asks him to forge a sword for him first. Vulcan agrees and leaves them alone.
Shadow asks Wednesday if Vulcan is trustworthy and confronts him about how Vulcan knew Shadow had been lynched by Technical Boy. Wednesday claims he said nothing but the New Gods also knew about the lynching. He is going to have Vulcan make a weapon to deal with it.
Deep within the factory and over vats of liquid metal, Vulcan forges Wednesday's sword. Wednesday compliments Vulcan on his craftsmanship, favoring it over the manufactured guns Vulcan now makes. Vulcan tells him that he gets more blood spilled in sacrifice with bullets than with blades and Wednesday could use a blood sacrifice of his own. He questions why Wednesday is starting this war and says it sounds like Wednesday is the only one benefiting. Wednesday asks if Vulcan told the New Gods they were in town and Vulcan confirms they are coming. They put power back into Vulcan's hand when he was just a forgotten story and now he is prayed to with bullets. He calls Wednesday a martyr but Wednesday denies it, saying it is actually Vulcan's role. Vulcan pledged allegiance to Wednesday and forged him a blade and the New Gods killed him for it. Wednesday swings the blade and slices Vulcan's head off. He kicks Vulcan into the vat below and watches as he dissolves. Shadow is freaking out as Wednesday hands him the blade and unzips his pants. He urinates into the vat to curse the bullets made.
Mythological Weapons: The bullets from his factory were able to kill an incarnation of Jesus. Vulcan also forges a sword for Mr. Wednesday that can kill other gods. Wednesday uses this god-forged weapon to behead Vulcan in "A Murder of Gods," resulting in Vulcan's death.
Reality Manipulation: In order to further sustain himself, he makes human sacrifices by having employees at his factory fall into his smelter by what looks like "accidents."
Telekinesis: In "A Murder of Gods," the bullets falling from the skies magically avoid both him and Mr. Wednesday, showing that he is able to redirect them.
He’s a brand-new addition who came from an experience Neil had. He was going through a small town in Alabama where he saw a statue of Vulcan. It was a steel town and, as he told the story, there was a factory that had a series of accidents where people were killed on the job and they kept happening because an actuarial had done the numbers and realized that it was cheaper to pay out the damages to the families of people who lost people, rather than to shut down the factory long enough to repair, and that occurred to him as modern a definition of sacrifice as there might be.