Nightmare is the leader of the Bad Sanses, and is often depicted as a cold, ruthless, and apathetic destroyer that relishes in the suffering of others. While some of this may be true, he isn’t fully heartless, and is actually capable of caring for others; his subordinates, for example. Nightmare is a cunning, smug, and strategic individual that is the second smartest of his team, with Error being the most intelligent one. He dislikes his brother, Dream.