Cross The Streams is a binary determination puzzle in which the cells in a grid are split into either shaded or unshaded.


The objective is to shade some cells, subject to the following rules:

  1. All shaded cells must connect horizontally or vertically upon completion.
  2.  No 2x2 area of shaded cells is allowed.
  3. Numbers to the left/top of the grid match with connected shaded cells in the respective row/column, in order. The length of these groups of connected shaded cells is equal to the value of the clue, separated by at least 1 unshaded cell.
  4. A question mark (?) represents a single clue whose value is unknown.
  5. An asterisk (*) represents any number of unknown clues, including none at all.


A standard 10x10 cross the streams and its solution.

Cross The Streams Example

Cross The Streams Solution