Examples of tropes or motifs

https://www.youtube.com/watch?v=kks_oIlVBI4 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.