Lich

Liches are commonly described as undead sorcerers. Wizards and even kings who strive to triumph over death by preforming various rituals that binds their intellect towards an artifact that they carry- known as a phylactery; to obtain a form of immortality, although, at the cost of their humanity. Even though they are immortal, they are corpses that rot over time, making them somewhat frail, even if they retain their intellect, they will slowly lose their memories, their passions and motivations until they lose all sense of purpose. 

Their immortality becomes a curse rather than a blessing, and they simply become like statues, remaining still forever in a void of indifference, while others malignant and eager to harm any living creature in their vicinity with dark magic.

Liches can be destroyed and freed from their curse, by burning them or destroying their phylactery, yet attempting to do so is dangerous. They are deadly foes that can use dark magic to inflict wounds that won't heal, for it seems that their dark magic can dilute and stain the soul of a living being, much like an infection. 

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