Codebreaker 25, Puzzle special, July 22
The solution for Codebreaker 25 in our Puzzle special, July 22, was incorrect. Click here to see a pdf of the correct solution for this puzzle. Apologies for any frustration.

The grandmaster and the rookie
Nigel Short, Britain's most successful player ever, starts a new career as the Guardian's chess columnist. His greatest challenge will be to transform Guardian journalist Stephen Moss - who admits to being 'truly hopeless' - into a half-decent player. Follow their progress here.

Interactive crosswords
Pit your wits against our top crossword compilers. An annual subscription of just £25 gives you access to new Quick and Cryptic crosswords every day, plus Guardian Unlimited's exclusive Quiptic and Genius puzzles. Click here to try the free archive puzzle, updated every Monday, and here to get 33% off our new mobile phone crossword service.

Fantasy Chairman
As chairman of your own fantasy football team, you get to hire and fire 11 players and a manager. Each squad costs just £6 and you'll be competing for a top prize of £10,000, plus fantastic monthly prizes. You can also set up a friends' league.

Sudoku classic
Give your brain a workout with our hand-crafted Sudoku puzzles. Visit this page every day, print the pdf of the most recent puzzle and fill in the grid. If you need a helping hand, call our solutions line on 09068 338 228. (Calls cost 60p per minute at all times. Service supplied by ATS.)