If you have a physical keyboard the following keys are available:

Colour the selected square:

  • a aqua
  • b blue
  • f fawn
  • g green
  • o orange
  • p pink
  • c clear all coloured squares

Load the next puzzle:

  • v very easy
  • e easy
  • m medium
  • h hard
  • d diabolical

Provided you have used the "fill in pencils" button:

  • s colour numbers that occur singly in a row, column or box
  • t colour all the twos
  • x check for an X-wing
  • y check for a Y-wing

A number key will pencil in the selected square.

choose your level