Aurgentum the Dog was an antagonist in The Chaos Chronicles.
Prior to her death, Aurgentum was a beautiful golden furred dog with blue eyes and a white muzzle. After her time in the Netherworld and transformation into a Hellhound, Aurgentum now has a scarred, mutilated, demonic face and body. Her fur has turned black as the night and her eyes as red as blood.
Aurgentum was once a caring person. However, her time in the Netherworld turned her dark. Aurgentum was fueled by vengeance and rage after becoming a Hellhound. She was also highly manipulative, fooling Noon and everyone else around her about her true form.
Aurgentum was once a member of Omega Squad, alongside Noon the Echidna, Nails the Bat, and Jonathon the Wolf. Aurgentum loved Noon ever since they were children and he loved her. They had a very intimate relationship which seemingly ended due to an argument. Aurgentum then found solace in Jonathon, but later rekindled her romance with Noon after Jonathon became overly possessive. Aurgentum took her chance of leaving Jonathon by enrolling in an art school in Soleanna. She kissed Noon and hugged Nails before she left. When she was packing her bags, she got into a fight with Jonathon, who hit her in the face. Aurgentum stormed off out of the G.U.N. Fortress.
Aurgentum then met with Robert the Wolf, a friend of hers. However, he was loyal to Jonathon, and he had ordered Robert to kill her. Robert severely wounded her, but could not do the killing blow on his beloved friend. Aurgentum went to a sacred space, the Master Emerald Altar on Angel Island, and begged Chaos to save her. The god did so, until she was found by Sheriff Cale the Cat. Cale brought her to the hospital in Central City where Doctor Jason the Squirrel was performing surgery on her. Aurgentum died due to internal bleeding. She was catalogged as 'Jane Doe' due to the high amount of blood and dirt on her, which caused her to become unrecognizable.
Aurgentum spent nearly five years in the Fields of Damnation in the Netherworld. She gave into the darkness around her and became a Hellhound. Aurgentum returned to the world of the Living when an abyss to the Netherworld opened on Angel Island. She found Noon at the shrine, and hugged him.
Aurgentum rejoined G.U.N. and rekindled her relationship with Noon. She led Thorn to discovering The Wolf Pack had kidnapped Midnight. Aurgentum displayed affection to Noon very openly, causing pain to Nails. The day before Halloween, Aurgentum was invited to Lana the Cat's party by Honey. She also witnessed Honey drawing, and looked disconcerted. She attended Lana's party, and eavesdropped on Lana's conversation with Thorn on Lana being a virgin. Aurgentum then cornered Lana in the elevator in her Hellhound form. When Honey was in the hallway, Aurgentum surprised her and knocked her out, putting her in the funhouse of mirrors. Aurgentum said that Honey wasn't a sacrifice, only a "girl who knew too much". Aurgentum then expressed disbelief at the revelation of Honey being a Reaper, a harbinger of Death. She then took Cale as he tried to save his daughter from her. Aurgentum appeared at the hospital, taking Jason as her next sacrifice. Aurgentum later took Duke and Alexandria the Hedgehog, Rose the Hedgehog's parents as the final two sacrifices. She brought them to Angel Island and tied them all up. Aurgentum then killed Robert and Emily the Wolf and incapacitated Elizabeth the Wolf and knocked out Cocoa the Dog. She claimed that she killed the two wolves in order to stop them from killing others. Aurgentum swayed Noon to her side and fought Jonathon and Thorn at the Mystic Ruins. She was severely injured by Jonathon.
Aurgentum managed to get to the Master Emerald Shrine. She begged Chaos to save her once again. Chaos created a water-tentacle and reached out to her, but before she could touch it, she was turned around by Nightshade the Fox. The two exchanged harsh words, and Nightshade then slashed her throat open. Aurgentum's blood spilled onto the altar.