Ace Adversary Achievement
Play 200 words in all your games.
These achievements require that you take a total of 50, 100, and 200 turns. A turn could be playing a word, passing your turn, swapping your tiles, or resigning the game. This achievement is not actually related to how many words you play. You can check your progress towards this achievement in the Statistics screen from the Main Menu. Look at the "Moves Played" stat. Thanks to Creech for clarification on this achievement.