Logic Masters Deutschland e.V.

A closed loop is to be drawn into the puzzle, which passes through all the cells with circles. White circles may be blackened. The sections of the loop run horizontally and vertically from cell center to cell center. In cells with a black circle, the loop must turn at a 90° angle and go straight through the fields before and after it. It must go straight through fields with a white circle and turn at a 90° angle in at least one of the fields before and after it. The loop must not pass through any cell more than once.

The loop does not pass through cells with numbers. A number indicates how many of the adjacent cells are used by the loop. These cells must be adjacent to each other vertically or horizontally, but do not necessarily form a contiguous part of the loop. There must be at least one empty cell between different groups of loop cells around a number cell.