anagram vs conundrum

anagram

noun
  • A word or phrase that is created by rearranging the letters of another word or phrase. 

verb
  • To form anagrams. 

conundrum

noun
  • A difficult question or riddle, especially one using a play on words in the answer. 

  • A difficult choice or decision that must be made. 

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