Can you crack the code? A Codeword (or Mots codes in French) puzzle is a completed crossword where the letters have been replaced with the number 1-26. Each puzzle will contain all letters. The goal of the puzzle is to crack the code and figure out which numbers correspond to which letters. In all but insane mode, you are given some initial letters to help get you started. Codeword Challenge provides an unlimited number of Codeword puzzles of varying difficulty for you to solve.