Nitemare, known as Card Majin (カード魔神 Kādo Majin, Card Demon God) in the Japanese version, is the main antagonist in a few of the Yu-Gi-Oh! video games. He has a less powerful form, DarkNite, which he usually appears as at first. In the Japanese versions, DarkNite is referred to as "Card Majin", while Nitemare is referred to as "Card Majin (true form)". A majin is a malevolent deity that causes misfortune and disaster. Kazuki Takahashi included line art for Nitemare, along with other rough sketches for cards for the real life card and video games in Yu-Gi-Oh! Duelist volume 11.