Logic Masters Deutschland e.V.

As night falls over the town square, a big Christmas Tree stands ready to be lit. To bring it to life, you must place the digits 1 through 9 exactly once in every row, column, and 3×3 neighborhood of the town square.

The green branches of the tree twist upward following the ancient German Whispers enchantment: any two lights that touch along a branch must glow with digits at least 5 apart.

At the very top sits the tree’s Golden Star, marked by a yellow cell with arrows pointing inward. Its digit must shine more softly than all the digits in the neighboring cells that touch it along an edge.

Under the tree, You can find four colorful Gifts, each wrapped in a shaded square. Every gift hides an even digit, waiting to be discovered.

Hanging from one of the branches is a Star Ornament, drawn as a yellow X. Its magic binds the two digits it connects so that together they always sum to 10.

Some branches hold bright Red Baubles, resting at corners between cells. Each bauble shows a set of digits, and every digit inside a bauble must appear at least once in the cells touching it.

Looping around the tree are sparkling Garlands, shown as red Renban lines. Digits along a garland must form a set of consecutive, non-repeating digits, though they may appear in any order.

And tonight, as the celebration begins, snowflakes drift gently through the square. These are shown as white dots, and any two digits separated by a snowflake must be consecutive.

Bring all these elements together, and the Christmas Tree will light up in full festive glory.