Examples of tropes or motifs that recur in stories

  Can you think of more examples of tropes or motifs that recur in stories? Post your example of a motif or trope that recurs in at least 2 different stories you're familiar with. Be sure to clearly explain the features that make your example an identifiable motif, and note the two stories in which you find this motif. Title your post descriptively, identifying the motif you discuss.