Name: Copper Gender: Male Appearance: A head in the shape of a large copper ingot, wearing old and shabby plumber's overalls. Usually, he is an ordinary plumber wandering the city repairing pipes, but in the shadows, he is a veteran killer who has never failed a mission. He leaves no trace with his perfect cleanup, and his appearance, behavior, and speech are so ordinary that even the Killer Association fails to notice his presence. His ordinariness, which attracts no one's attention, is his greatest weapon.

Name: Iron Gender: Female Appearance: A head in the shape of a large iron ingot, wearing silver armor. She is Gold's longtime childhood friend and loyal knight. Even after Gold ascended the throne, she advised him to walk the right path. However, when Gold exiled his younger brother Netherite to the Nether to protect his throne, she was disappointed, and their relationship soured. Nevertheless, she hasn't completely abandoned Gold and intends to stay by his side to monitor and guide him so he makes no more wrong choices.

Name: Gold Gender: Male Appearance: A head in the shape of a giant gold ingot, wearing a golden crown and ornate royal robes. He was a benevolent and kind monarch to his people. However, he was different toward his only blood relative, his younger brother Netherite. Hating to have his possessions taken away, he was seized by the anxiety that Netherite, who would one day become stronger than him, might even take the throne. Ultimately, he cut off one of his brother's arms and exiled him to the lawless Nether. While he was a merciful king to his subjects, he was a cold-hearted brother who would do anything to protect his position.

Name: Netherite Gender: Male Appearance: A head in the shape of a giant netherite alloy ingot, wearing tattered royal robes and a netherite prosthetic arm. Born with immense martial power, he grew up having everything taken from him by his older brother, Gold, since childhood. Fearing the throne would be stolen, Gold severed one of his arms and exiled him to the lawless Nether. Netherite conquered the Nether with his overwhelming strength and grew his forces, replacing his lost arm with a prosthetic. Finally returning to the original world, he begins to move to take revenge on the brother who abandoned him.

Name: Amethyst Gender: Female Appearance: A head in the shape of a giant amethyst, wearing a purple suit, tie, and tie pin. She grew up with every action, from human relationships to minor interests, controlled by her father, Lapis Lazuli. While learning magic under her father, she met Copper at the magic school, who received no attention from anyone. She had a pleasant conversation with Copper, the first person to pique her interest, but thought she would never see him again after he was "warned" by her father. However, she found Copper at school again the next day and developed a deeper interest. Later, the two began working together as killers in the shadows.

Name: Lapis Lazuli Gender: Male Appearance: A head in the shape of a giant lapis lazuli, wearing archmage robes. Born into a wealthy family, he became an archmage through natural talent and lived happily with his wife, Ruby, and daughter, Amethyst. However, tragedy struck. He lost his wife in an accident caused by his best friend, Blaze Powder. Since then, seized by the fear that he might lose his daughter in an instant, he began to strictly control every action of Amethyst.

Name: Emerald Gender: Male Appearance: A head in the shape of a giant emerald, wearing a green hoodie, a white coat, striped pants, a monocle, and golden shoes. Emerald is a merchant prince with immense influence. He can see the value of a product at a glance and uses his brilliant eloquence to charm others into closing the deals he wants. Rumors say there is no product that hasn't passed through his hands. However, even he, who seems perfect, has a fatal weakness: his sense of fashion. He wants to spread his fashion to the world, but his own attire is bizarre to anyone who sees it. Unlike his business acumen, he has no talent for fashion whatsoever.

Name: Diamond Gender: Male Appearance: A head in the shape of a giant diamond, tall and bulky, wearing high priest robes. Diamond is the leader of the Diamon religion, which saves those in need. Diamond possesses the power of immortality and has saved many non-humans over a vast amount of time. He never intervened in matters unrelated to the Diamon religion. Even now, Diamond continues to save those who are suffering.

Name: Redstone Gender: Male Appearance: A head in the shape of a giant redstone, wearing copper glasses and orange clothes. He is an engineer. He has loved working with machinery since he was young and is currently collaborating with Emerald. He occasionally makes weapons, which he gives to his friend Copper.