Logic Masters Deutschland e.V.

That shrimp didn't stand a chance.
Exhausted, you curl up against the frozen ground and close your eyes, praying that they will open to the sound of your ringing alarm clock and that you'll be back in your bed, blankets tangled.
Instead, you wake to another sound. A low, distant call, rolling through the cave like something dragged out of the dark, creeping through the thick fog that had formed while you slept.

"BOB!"

It bounces off the walls, stretching, warping, doubling back on itself until you can't tell if it's coming toward you or retreating. Is someone calling you? Is that... your name?

"Hello?" you shout.

Nothing answers except the ice itself, crackling, the cryptic fog swallowing its sound almost instantly as it thickens around you. You lift your beak and breathe in. There is that scent again, faint but unmistakable: a shrimp. You lower yourself onto your belly and follow the scent into the white. If a voice can reach you, there must be a way out, and that shrimp may be your only clue to find it.

You start sliding carefully. You are on thin ice.

Normal 9x9 sudoku rules apply, except with digits 0-8.

ICE SLIDING: Draw a path from Bob the penguin to the shrimp. The ground is covered in turquoise slippery ice. When Bob starts sliding in a direction it can not stop until it hits an obstacle (a wall or a rock) and stops in the preceding cell. The path can then turn in any available orthogonal direction and continue until the next obstacle. The path can cross itself but not overlap. See example below.

ROCKS: There are 9 rocks in this grid. No rocks share the same row, column or 3x3 box. Digits on rocks indicate the number of cells visited by Bob in the corresponding 3x3 box. A cell visited multiple times counts for one. Rocks can't be on thin ice.

THIN ICE AREAS: A thin ice area can only be entered once. The sum of the digits visited by Bob in a thin ice area must be lower than or equal to the sum of the digits not visited by Bob in that thin ice area. Digits may repeat in a thin ice area if allowed by other rules.

DYNAMIC FOG: Entering correct digits may clear fog somewhere in the cave. No guessing is necessary.

There are multiple paths to the shrimp. In this puzzle, find the only penguin's path that is a valid REGION SUM LINE (box borders divide the line into segments with equal sum).