Created in the early 13th century, the Codex Gigas is the world’s largest surviving medieval manuscript—famed for a full-page portrait of the Devil said to have cursed its author. Legend claims a monk condemned to death wrote the entire book in a single night after making a pact with Satan, resulting in the eerie, uniform script with no sign of fatigue. Containing the Bible, medical texts, and exorcism rituals, it was once blamed for misfortune wherever it traveled. Now held in Stockholm, the “Devil’s Bible” continues to attract researchers and occult enthusiasts.