Here is the full list of all 57 Sudoku Zenkai achievements.
Played 50 games with a friend.
Completed 50 games.
Played 10 Zenkai games.
Completed a daily challenge with a friend.
Completed a game after 60 minutes!
Completed a game after 120 minutes!
Played 20 games with a friend.
Completed a 20 winning streak.
Played a game with every emblem.
Played a game with every theme.
Completed a Fair Sudoku without any helps!
Shared 20 games.
Played 10 Insane games.
Played 10 Challenging games.
Played 10 Fair games.
Played 10 Trainee games.
Shared 15 games.
Completed 20 games.
Completed a Insane Sudoku under 20 minutes.
Completed a Insane game with a friend.
Completed a Insane Sudoku without any helps!
Completed a Trainee game with a friend.
Completed a Zenkai Sudoku without any helps!
Completed a Challenging Sudoku without any helps!
Played 10 games with a friend.
Shared 10 games.
Completed a Pushover game with a friend.
Played 10 Pushover games.
Completed a Pushover Sudoku under 7 minutes.
Completed a 10 winning streak.
Completed a game using Last Valid Board.
Completed a Pushover Sudoku without any helps!
Completed a Trainee Sudoku without any helps!
Shared 5 games.
Completed a Zenkai game with a friend.
Completed a Challenging game with a friend.
Asked a friend for help.
Played 5 games with a friend.
Helped a friend.
Completed a Fair game with a friend.
Played 1 games with a friend.
Completed a Challenging Sudoku under 15 minutes.
Played a game with 2 different themes.
Shared 1 games.
Completed 10 games.
Completed a game with another emblem.
Completed a game after 30 minutes!
Completed a game using a hint.
Completed a Fair Sudoku under 10 minutes.
Completed 5 games.
Completed a 5 winning streak.
Completed a Trainee Sudoku under 5 minutes.
Completed a 3 winning streak.
Completed a daily challenge.
Completed a Zenkai Sudoku under 30 minutes.
Completed a game without using annotations.
Completed 1 game.