Sudokuwiki.org's Weekly 'Unsolvable' Sudoku #646

In this post I'll be tackling the weekly "Unsolvable" puzzle from SudokuWiki. This week's puzzle was provided by Andrew Stuart. 

Puzzle String: .5.....82...6......21..73...9.4....8.78....3.1....9.5...29..84......5...93.....7. - Sudoku.Coach

SE: 9.0

Another Andrew Stuart puzzle so I'm hoping it will be on the easier side like the last one. 

After basics:
Finned Swordfish

(1=349)r1c456 - r1c3 = r2c3 - (9=1)r2c8 => r1c7, r2c56<>1

(5)r7c9 = (5-7)r7c1 = r7c5 - r4c5 = r6c45 - r6c9 = (7)r2c9 => r2c9<>5

(2)r9c456 = r9c7 - (28)(r6c7 = r6c45) - (7)r6c4 = (7)r8c4 => r8c4<>2

(4=8)r2c2 - r2c6 = (8-4)r9c6 = (4)r12c6 => r2c5<>4

(7)r4c7 = r4c5 - r7c5 = (7-5)r7c1 = r7c9 - r3c9 = (5)r2c7 => r2c7<>7

(38)(r6c3 = r6c45) - (7)r6c4 = r8c4 - (79)(r8c3 = r12c3) => r12c3<>3

(1=6)r7c2 - (6=371)b8p234 - r9c456 = (1)r9c79 => r7c9<>1

(28)(r6c7 = r6c45) - (7)r6c4 = r8c4 - r7c5 = (7-5)r7c1 = r9c3 - (5=364)b4p389 => r6c7<>4


Almost-ALC tie Almost Kraken X-Wing: [(4=8)r2c2 - r23c1 = (8-4)r8c1 = r123c1-] = (4)r5c1 - (4)r5c7 = [(4)c67\r12 = (4-8)r9c6 = r2c6 - (8=4)r2c2] => r12c3<>4

Fairly sure I've run out of easier steps now. Wasn't sure I could get any eliminations off this almost-ALC but found a way to make it work using this double-Kraken X-Wing.

(5)r2c7 = r9c7 - r7c9 = (5-7)r7c1 = r7c5 - r4c5 = r4c7 - r6c9 = r2c9 - (7=19)r2c38 => r2c7<>19


Kraken AHS AIC: (7)r4c5 = r4c7 - r6c9 = (7-1)r2c9 = r2c8 - (1)r4c8 = [(17)(r4c5 = r4c67) - (1=256)r5c456] => r4c5<>256

(25)(r5c1 = r47c1) - (7)r7c1 = r7c5 - r8c4 = (7)r6c4 - (28)(r6c4 = r6c57) => r5c7<>2

(8)r6c5 = (8-7)r6c4 = r8c4 - r7c5 = (7-5)r7c1 = r9c3 - r4c3 = (5-2)r4c1 = r5c1 - (2=156)r5c456 => r6c5<>6

(8)r9c6 = r2c6 - (8=5)r3c4 - r5c4 = (5-6)r5c5 = r789c5 => r9c6<>6


Kraken Cell: (6)r4c8 = [(6=152)r5c456 - r5c1 = r4c1 - (2=1)r4c8 - r2c8 = (1-7)r2c9 = (7)r6c9 - (49)(b6p9 = b6p46)] => r5c79<>6


Kraken Cell: (6)r13c1 = r1c3 - (6)r4c3 = [(5)r7c1 = r4c1 - (5=3)r4c3 - (3=467)r6c239 - r6c4 = r46c5 - r7c5 = (7)r7c1] => r7c1<>6


Kraken Cell: (6)r4c8 = [(2)r5c1 = r4c1 - (2=1)r4c8 - (1=9)r2c8 - r2c3 = (9-6)r1c3 = (6)r13c1] - (6)r5c1 = (6)r5c56 => r4c6<>6


Kraken Sashimi X-Wing: (4)r36\c19b4 = r3c5 - r89c5 = (4)r9c6 - (28)(r9c6 = r245c6) => r5c45<>2


Kraken Row: (4)r3c1 = [(4)r5c7 = r12c7 - r3c9 = r3c5 - r12c6 = (4-8)r9c6 = r2c6 - (8=5)r3c4 - (5=194)r5c479] => r5c1<>4

Triple

(7)r1c7 = (7-1)r2c9 = r2c8 - r4c8 = (1)r4c7 => r4c7<>7

Hidden Pair

XYZ-Wing

(3)r1c4 = r6c4 - (3=2)r4c6 - r4c78 = (2-7)r6c7 = (7-6)r1c7 = (6)r1c1 => r1c1<>3

(1)r4c7 = r4c8 - (1=9)r2c8 - r8c8 = (9)r8c7 => r8c7<>1

(2)r9c4 = r6c4 - (2=3)r4c6 - r4c3 = (3-4)r6c3 = r6c2 - (4=8)r2c2 - r2c6 = (8)r9c6 => r9c4<>8, r9c6<>2

Triple

(6)r9c7 = r9c9 - (6=7)r6c9 - r6c7 = (7)r1c7 => r1c7<>6

(8=4)r2c2 - r6c2 = (4-3)r6c3 = r4c3 - (3=2)r4c6 - r2c6 = (2)r2c5 => r2c5<>8

(1=9)r2c8 - (9=2)r2c5 - r2c6 = r4c6 - r4c8 = (2)r8c8 => r8c8<>1

(9=7)r1c3 - r1c7 = (7-2)r6c7 = r6c5 - (2=9)r2c5 => r2c3, r1c5<>9

XY-Wing

(2=9)r2c5 - (9=1)r2c8 - (1=6)r4c8 - (6=2)r6c7 => r6c5<>2

STTE

Again not as difficult as the Kröger puzzles, this one only took me a few hours. That's how long some single steps took in the 9.4 a few weeks ago lol. Some satisfying moves in this week's solve, I think the almost-ALC was the best, but that reminds me I forgot to use the actual ALC when it became available. Whoops!

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