XXI puzzles require a sum of 21 in every row and column. Move the gems around on the board until a solution is found. All gems have a unique numerical value, but watch out for the special gem that can be either a 1 or 11. Puzzles get harder as you progress your way through all 200 levels. Can you become a XXI champion? FEATURES - 200 Unique & Challenging Puzzles - Game Center Achievements (V, X, L, C, CC) - Game Center Leaderboard for Highest Level - Beautiful Music, Sounds, and Retina Graphics - Universal App looks Great on iPhone and iPad - Share Solution Photos with Friends Thanks for playing XXI by TMSOFT and good luck! Website: https://www.tmsoft.com/xxi/