guessing game vs mystery

guessing game

noun
  • Any game the object of which is for a player or players to guess a word, etc, for which the other player or players provide clues. 

  • A situation in which there is insufficient information, requiring participants to rely on conjecture. 

mystery

noun
  • Something secret or unexplainable; an unknown. 

  • Someone or something with an obscure or puzzling nature. 

  • A religious truth not understandable by the application of human reason alone (without divine aid). 

  • A particular event or series of events in the life of Christ. 

  • A sacrament. 

  • A secret religious celebration, admission to which was usually through initiation. 

  • A craft, art or trade; specifically a guild of craftsmen. 

How often have the words guessing game and mystery occurred in a corpus of books? (source: Google Ngram Viewer )