D4C, or "Dirty Deeds Done Dirt Cheap," is a fictional ability from the manga and anime series JoJo's Bizarre Adventure. It allows its user to travel between alternate dimensions, creating a unique and complex narrative where different versions of characters can interact. This power is primarily associated with the character Funny Valentine. The ability is notable for its strategic implications in battles, as it can manipulate reality and outcomes by accessing different universes. D4C's mechanics involve the concept of "parallel worlds," where slight variations of events lead to diverse possibilities, making it a key element in the storyline of Steel Ball Run.