Deus ex Machina

A deus ex machina is a plot device, commonly used when an author has written themselves into a corner. It is a way to "save the day" by random, often by magical or pseudo-magical means. For example: Our heroes are trapped in the last room of a keep, hordes of bloodthirsty orcs pounding down the door, with a dragon roasting the stones around them. Suddenly, God whisks them away to a magical island paradice. Dei ex machina are often used by 'Sues.