suguru puzzle   tectonic puzzel

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Kurotto literally means "black units" and is a logical puzzle published by Nikoli. The task consists of a grid with circles in some cells. A circle can contain a number or not. The task is to blacken cells according to the following rules:

  • Make cells black so that each circled digit represents the total number of black cells in connected groups that share a border with that circled digit.
  • Cells with circles cannot be black.
  • Cells with circles without a number: you don't know the total of number of cells in connected groups.

Follow the steps below to solve a Kurotto puzzle from our database.

  • LEV: the number of puzzles available is in parentheses.
  • PUZ: enter the number of the puzzle that you want to make.
  • START: the puzzle of your choice will now be loaded.
  • Click on to go to the next Hashi puzzle.
  • Click on a blue cell to make it black .
  • Click on a black cell to make it white .
  • Click on a white cell to make blue and neutral.
  • The puzzle is ready if you only have black and white cells.
  • Click ✓ to check the puzzle. The wrong cells turn red.
  • Click SOL to display the Kurotto puzzle solution.