Ravenloft - The Dark Powers
The following text incorporates content from Wikipedia.
The Dark Powers are a fictitious malevolent force from the Ravenloft campaign setting for the Dungeons and Dragons fantasy role-playing game. Their exact nature and number are purposefully kept vague, allowing for plot development in accordance with the Gothic tradition of storytelling - where the heroes are frequently outclassed and outnumbered by unknowably evil forces beyond their control.
The Dark Powers most frequently serve as a plot device for Ravenloft, especially concerning the Dark Lords, the de facto visible rulers of the Ravenloft Demiplane. Where the players are often tormented and opposed by the Dark Lords, the Dark Lords are themselves tormented and opposed by the Dark Powers. Of course, the difference lies in order of power - while many D&D adventures focus on allowing a band of heroes to prevail over a Dark Lord (much as in the spirit of Bram Stoker's novel Dracula), no such victory over the Dark Powers is conceivable.
Most frequently, the Dark Powers make their wishes and intents known through subtle manipulations of fate. Thus, Strahd von Zarovich's many attempts to win back his love, Tatyana, are doomed to failure, but the Dark Powers arrange such that he never truly loses hope. Each time, for example, Strahd's own actions may be partially culpable for his failure, and as such he may go through crippling self-recrimination, rather than cursing the gods solely and giving up. Most other Dark Lords have similar tales of frustration, kept all the more unbearable because the flicker of the possibility of success is never truly extinguished.
Not all Dark Lords acknowledge the Dark Powers directly, however. Strahd, for example, in his own memoirs, speaks only of a force known as "Death", who mocks him with the voices of his family and former colleagues throughout his life. Vlad Drakov, whose military expeditions are doomed to constant failure, seems even to be totally oblivious of any non-mortal factors in his repeated defeats.
The Dark Powers also seem capable of non-evil manipulations. Although their machinations are often directly responsible for the misery of many of Ravenloft's inhabitants, they also appear to play a role as dispenser of justice. Some tales of innocents, who have escaped Ravenloft for happier environs, are attributed to the Dark Powers, who have judged a being worthy of reward and release from their misty domain.