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Study guides

24 short guides, one for each kind of puzzle at Levels 6–10: the idea, the steps, examples, what to watch out for, and a few to try. The same guides are in the app.

Level 6 · Master

• Age puzzles
• Line-ups
• What must be true?
• Truth-tellers and fibbers
• Two rows woven together

Level 7 · Code Breaker

• Fruit codes
• Letter rows
• Lock codes
• Number codes
• Shift codes

Level 8 · Detective

• Who did it?
• Round tables
• Truth-tellers, four people
• Five-friend clue puzzles

Level 9 · If–Then

• What cannot be true?
• If–then
• Only if
• Switches and lamps
• Unless

Level 10 · Grandmaster

• Long line-ups
• 4-digit locks
• River crossings
• Chain scales
• Harder truth-tellers