Logic Masters Deutschland e.V.

If you enjoy this puzzle, please check out Killer Octopus, which has a similar (and, mercifully, more concise) ruleset!


Any resemblance to my three-month-old daughter, including name, is purely coincidental, and has nothing to do with how it feels when she's flailing around impatiently for a bottle that we're half way through preparing for her.

Rules:

Hi, I'm Orla the Octopus! Please can you help me grow in muscle and mind?

Here in Seadoku, every row, column and 3x3 box contains the same set of nine digits, chosen from 1-9, but this set might repeat some digits and omit others.

Help me to grow my eight tentacles! They will grow orthogonally and/or diagonally between cells from my head (r5c5) until they reach the edge of the grid, where they stop. Each pair of opposite tentacles can be considered as a line, which must have 180-degree rotational symmetry around my head. All my tentacles will pass through the same number of cells, and they cannot cross or overlap each other, except at my head.

Help me learn some maths! Each line (pair of opposite tentacles) must exhibit one (or more) of the following properties, with each property appearing on at least one pair of tentacles:

- ZIPPER: the digit in my head shows the SUM of digits an equal distance from my head.
- ZIFFER: the digit in my head shows the DIFFERENCE between digits an equal distance from my head.
- MULZIPLIER: the digit in my head shows the PRODUCT of digits an equal distance from my head.
- ZIVIDER: the digit in my head shows the QUOTIENT of digits an equal distance from my head.

Digits separated by a black bubble are in a 1:2 ratio.
Digits separated by an X sum to 10.
Digits separated by a V sum to 5.
An inequality sign points to the lower of two digits.