Kokushibo's Blood Demon Art, Crescent Moon Blades, allows him to create and control unpredictable crescent moon-shaped blades from his flesh katana. These blades, formed from his blood, constantly change in size and speed, making his attacks difficult to anticipate. The power of his techniques is greatly enhanced by this ability, and he can generate blades even without swinging his sword. Kokushibo's volatile Blood Demon Art poses a formidable challenge for Demon Slayers.