As is seen in-game, Swan summons five zombies to Earth from the Rotten World. As informed by Sensei Morikawa, it is said that the Rotten World is full of zombies, these in which Swan has summoned by ritual.
Unlike most zombie known in popular media, the Dark Purveyors posses whimsical abilities that go beyond the expected limits of a zombie. They are the most sentient zombies of the game and as proclaimed by Swan they are capable of rotting anything in their path, transforming anything into the undead. Each Dark Purveyor's unique abilities or powers are primarily determined by that of their music genre.
Each boss is also capable of counter-attacking each of Juliet'sChainsaw attacks, making them more difficult to kill. They are used as a sacrifice in order to summon a final zombie of the name Killabilly who is to reach Swan's goal to annihilate all of humanity. It is unknown whether or not Swan actually had control over them.
The history and origins of the Dark Purveyors are highly unknown prior to the events of Lollipop Chainsaw. All that is known is that they are supernatural zombies from the dimension of the Rotten World, and are all 18 of age.
During the events of the San Romero Zombie Apocalypse, a San Romero student of the name Swan summoned five malicious lords in order for him to become the God of a desolate Earth. Upon arrival, five colored, glowing orbs appear and presumably kill a determined Sensei Morikawa. These glowing orbs were revealed to be the Dark Purveyors, who upon arrival showed signs of loyalty and great respect towards Swan, hungering for a command in an rabid manner.
As Swan begins to proceed with his dark ritual, he commanded Zed to take his physical form and target Juliet in order to prevent her from stopping the other purveyors from infecting the rest of San Romero. He then scolds Juliet with his supernatural abilities, causing her and Nick to fly all the way to the Junkyard.
Once Juliet and Nick reach the Junkyard, they notice that Zed is already present, despite his previous location being from a much farther distance. As shown, Zed has already infected large quantity of civilians of San Romero, most of which are zombie teenagers who were currently listening to the music that was occurring at the pit. Zed's unusual abilities are then further explored, when he screams into his sudden microphone, causing demolished cars of San Romero to collapse around the area.
As Juliet persisted to his location, Zed began using his loud screeches in order to prevent her arrival, causing vehicles, words and various other objects to fall upon her. When Juliet finally manages to reach the stage, Zed is out of Juliet's reach of sight, unaware to his presence above stage. Zed then attempts to strike her, as she evades the sudden attack. Zed then formally confronts Juliet, later causing a fact screen to appear. As Juliet reads an influence, she becomes offended by the fact that Zed is abusive towards small animals. The first boss battle then begins.
After a brief series of repetitive slashes, Zed finally succumbs to Juliet's attacks and slowly dies as his body begins to split and scream painfully. Once deceased, Zed recites a mysterious speech in an unfamiliar language, while evaporating into spiritual energy.
Sensei Morikawa, who was presumed dead before the battle, returns grasping for life, as he walks towards Juliet to warn her about the last remaining Purveyors. He comes with bad news, claiming that the Purveyors have spread around San Romero and have successfully infected nearly every living thing in it. Any signs of life are currently quite scarce.
Before his death, he bring Juliet his word of luck and a gift for aid for the Zombie Apocalypse. Morikawa then passes and his soul then leaves his body into an elevator that then lifts up to an angelic sky that is presumed to be the Land Beyond Words.
After returning from The Junkyard, Juliet and Nick begin to discuss the very serious of issue Nick's bodiless condition. After Juliet obliviously refuses to acknowledge Nick's situation, Nick attempts to angrily explain his demands. But this is interrupted when blood suddenly lands on his face. Juliet's attention is then brought abrupt, as she begins to inspects the cloudy skies. A mysterious ship is then detected, revealing a great Viking zombie, with his pet and various other zombies that are providing the movement of the ship.
After meeting up Cordelia at the Swimming Pool, the ship suddenly takes sail and begins to abandon the area. Cordelia and Juliet successfully execute a clever maneuver, and Juliet then lands on the top of the ship. Once the two begin to confront, a boss fight begins.
The Viking is revealed to be a zombie of hysterical strength of the name Vikke. As the two battle, Juliet repetitively slashes through many of Vikke's mid-sections, until his head is decapitated, at which it then grows and reveals the true extent of his rage.
Once his jaw is dismembered, Vikke dies, shocked that he could be beaten by a girl. His pet Yumil desperately attempts to fend off Juliet for Vikke, but fails when a kick stops him. Vikke then repeats a phrase that was previously spoken by Zed, and begins to evaporate into spiritual energy. The ship then begins to lose control and lands at the O'Bannon Farm.
Once there Juliet seemingly awakens after the impact of the fallen ship. Looking around she discovers Nick is missing until he reveals to her that he had become a zombie, despite Juliet detaching him from his body. Nick then proceeds to attack Juliet, until the noise of Rosalind's bus makes her grow conscious. Juliet then finds Nick still on her waist, proving the previous events to be a nightmare. Rosalind then speaks to Juliet claiming she has appeared to rescue Juliet, until Rosalind loses control of her bus. Finding no Purveyor, Juliet begins to follow her sister, attempting to save her from possible harm.
Juliet will frequently encounter unusually large mushrooms along the way through the O'Bannon Farm that will teleport her into a mysterious psychedelic world where Giant Chickens are notable present. Once escaping she will always find herself back in a tractor at the O'Bannon Farm.
Once Juliet manages to catch up with an assumable Rosalind, she enters the bus expressing her gratitude for Rosalind's safety. When Rosalind explains that she managed to fix the bus, Juliet grows suspicious as Rosalind is not usually skilled in driving or cars.
After the bus abruptly shifts, Juliet notices from the rear-view mirror that Rosalind's appearance has changed. The bus is then suddenly engulfed by dark seals and the three are sent again into a mysterious world.
It is later revealed that this is another Dark Purveyor who has just recently kidnapped Rosalind and lured Juliet into her trap. After welcoming Juliet into Mariska's "world" a boss fight then begins. After a series of bubble attacks and center slashes, it is revealed that Mariska is capable of duplicating herself, by regenerating a split half.
Mariska is then defeated when her collar bone is destroyed and is decapitated after Juliet escapes her Psychedelia dimension. Her sitar gets destroyed and she repeats the peculiar phrase and evaporates into energy.
Juliet and Nick then inspect the area, and discover that Rosalind is missing. Juliet later gets a phone call from a mysterious stranger who then informs Juliet that he has kidnapped her sister at the Fulci Fun Center. Before they enter the risk, Juliet's father, Gideon suddenly appears for Juliet's aid while showing a disapproval for Nick.
When Juliet and her father reach the entrance of the Fulci Fun Center, they encounter zombies playing arcade games. Juliet then enters an elevator and is later sent to an alternate digital dimension reminiscent of video games. Juliet and Nick will enter this dimension frequently throughout the Fulci Fun Center until they manage to reach the roof of the building where the Dark Purveyor is holding her sister hostage.
Upon confrontation, Josey reminds Juliet that she must defeat him in return for her sister, in which Josey begins to attack her with the use of his mini UFO and gadgets upon the roof. After a brief slash across his waist, Josey abandons the Fulci Fun Center to continue the battle on his ship. Determined, Juliet follows Josey, provoked by his deceptive escape.
At his ship, he informs Juliet that he is going to send them to their impending doom to space. Before Josey can do this, he is easily defeated by Juliet when she breaks his shield and begins to break his UFO. Out of desperation, Josey deceives Juliet by informing her that his death will result in the loss of her sister. To his dismay, Gideon manages to get on the ship and parachutes to safety with an unconscious Rosalind. Josey, along with his ship, is split in half and repeats the same peculiar phrase that has been throughout the battles of San Romero.
After rescuing Rosalind, The Starlings and Nick reunite to maneuver a tactic in order to defeat the final Purveyor. The go to the unfinished Cathedral where Gideon punches a support beam, causing a domino effect to create a hole within the ground. Juliet then jumps into the hole, ready to confront the final purveyor.
At arrival, Juliet discovers Swan who oddly welcoming and glad for Juliet's presence. A bullet is then suddenly shot, and another Purveyor appears, firing bullets from a sudden blast of fire.
As Juliet is introduced to Lewis, the two then begin to collide their weapons. Lewis then threatens Juliet with his high confidence and begins to circle her, with the use of motorcycle and guitar.
After causing him to fall off of his vehicle and detaching his legs, Lewis then angrily reveals to Juliet the abilities of his motorcycle, when it begins to adapt into a "Elly-phant" mech form, where it grows legs, mechanical arms and a head. After a long series of veracious improvisational fights, Lewis finally succumbs to Juliet's attacks when Lewis' chest is slashed diagonally along with his bike. Lewis then dies an agonizing death and repeats the mysterious phrase that all of the Dark Purveyors have been exclaiming at the points of their deaths.
After he dies, Swan is still oddly glad that Juliet manages to kill Lewis Legend, despite his presumed purposes. It is later revealed to Juliet that her defeats against the Dark Purveyors, was a pre-determined plan to Swan's diabolical plot. He claims that the sacrifice of five pre-selected zombies was required to occur, and that by the point of their deaths they must exclaim:
Meus Vita, Rege, pro nefario coepto!
— My Life. King. for your dark enterprise!
After a flash back of all the sacrifices that Juliet had made, Juliet, so shocked, begins to question the intentions of Swan. He claims that Juliet's "betrayal" was the main motivation of his revenge, and that he wanted to make Earth a much more "rotten" world, by filling it with zombies.
Swan then shoots himself with Lewis' Guitar, so that he may become part of Killabilly. A blob of undead corpses clump together at the center of San Romero, and comes a giant named Killabilly.
After defeating all of the Purveyors, Juliet and Nick focus on Killabilly and try to save what's left of San Romero.
At their debut, the Dark Purveyors appears as pure energy, glowing, colorful orbs conducting electricity and having a dark smoke emitting from their orbs. During this form, the Dark Purveyors are still capable of speaking, but in an amplified and distorted tone.
Once the Dark Purveyors take their physical forms, they are openly distinguishable from the common Zombie enemy types seen commonly throughout the game. Unlike most Zombies in the game, the Dark Purveyors are capable of proper speech, physical stability and posses supernatural abilities that are exclusive to them.
They retain many human characteristics in their personality and physical forms, which include their notable capabilities of free will, showing signs of pure evil, as opposed to the San Romero Zombies, who have become amoral to the effects of the toxic fumes. A majority of the Dark Purveyors show little to no decay to their physical appearances (with the exception of Mariska) creating a sense that they are more human than just feral corpses.
After a fatal defeat, the Purveyors will lose their physical forms and manifest into a purple energy that will evaporate like smoke and spiral into the air to fully vanish. A purveyor is still capable of speaking during this form, repeating the infamous phrase:
Meus Vita, Rege, pro nefario coepto!
— My Life. King. for your dark enterprise!
Once this phenomenon occurs, the effects caused by the Dark Purveyors to a certain area vanishes, and it is unknown where these spiritual energies are transferred after death.
Each Dark Purveyor is a symbolic reflection of Swan prior to the events of the Apocalypse. Zed symbolizes Swan's grown new-found confidence and his ability of self-expression to show his personal opinions about the world. Vikke symbolizes Swan's emotional rage and how it helped him become determined in his diabolical plan.
Mariska symbolized what was left of Swan's inner kindness and sense of rationality that later became corrupted when he grew heart-broken by Juliet's new-found love interest. Josey symbolized Swan's social frustrations and his desires to become accepted by the popular crowd. Lewis Legend also symbolized his inner potentials, and unrealistic desires to become righteous and victorious in his dark scheme.
Despite deriving inspiration, from historical music genres, The Dark Purveyors also seem to be based on stereotypes of secular fears that associated with such music genres (such as Burzum vocalist Varg Vikernes burning down a church and Sex Pistols bassist Sid Vicious being accused of murdering Nancy Spungen).
The Dark Purveyors are vaguely similar to “The League of Evil Exes” from the Scott Pilgrim franchise. They formed because they both had an infatuated love for another, who left them, and seek vengeance on those who attain them.
The upside down pentacle formed by the ritual is also a symbol associated with dark magic.