Practice
Geometry

Non-Consecutive

Orthogonally touching cells can never hold consecutive digits.

Tips
  • Every placed digit forbids the two either side of it in all four neighbours.
  • Middle digits bite hardest: a 5 blocks 4 and 6, while a 9 only blocks 8.
  • Diagonal neighbours are unaffected — only shared edges count.
📖 Learn the rule first ▸
Drills