The Darkhold is a fictional book of dark magic in the Marvel Comics universe. It is often associated with the character Chthon, an ancient and powerful demon who is believed to have written it. The book contains spells, incantations, and forbidden knowledge that can grant immense power but also corrupt those who seek to use it. In various storylines, the Darkhold has been sought after by heroes and villains alike, including characters like Wanda Maximoff and Doctor Strange. Its influence can lead to chaos and destruction, making it a significant artifact in the battle between good and evil within the Marvel universe.