Some work towards crushing their opponents. The sadistic ones prefer to just step back and watch them suffer. This is "Cruel Mercy" - sparing one's enemy (or, in some examples, even actively keeping them alive) as a punishment rather than a reward. Usually, the villain or one of the hero's friends will ask "Why did you let me/him live?" Expect the hero to give a disturbingly vivid description of how they are actually being much, much crueler this way. Villains really should Beware the Nice Ones. Examples of Cruel Mercy include: