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`. . . | 4 2 . | . . .`

. . 6 | . . . | 7 5 .

. 4 . | . . 5 | 2 6 .

------+-------+------

. . . | . 1 7 | . 3 .

. . 5 | 8 . 4 | 6 . .

. 3 . | 5 6 . | . . .

------+-------+------

. 6 2 | 3 . . | . 4 .

. 1 7 | . . . | 9 . .

. . . | . 9 2 | . . .

57 57 1389 | 4 2 6 | 13 89 1389

12 29 6 | 19 8 3 | 7 5 4

138 4 1389 | 19 7 5 | 2 6 1389

---------------+--------+-----------

6 89 489 | 2 1 7 | 45 3 589

127 279 5 | 8 3 4 | 6 79 129

12478 3 148 | 5 6 9 | 14 78 128

---------------+--------+-----------

9 6 2 | 3 5 1 | 8 4 7

35 1 7 | 6 4 8 | 9 2 35

3458 58 348 | 7 9 2 | 35 1 6

I've found a single forcing net that reduces this puzzle to singletons (I set out looking for eliminations in the colored 3's and r1c7 looked promising):

r1c1-7-r1c2=7=r5c2=2=r2c2-2-r2c1=2=r5c1 (with r1c1-7-r5c1)... continues with r5c1=1=r5c9-1-r1c9 (with r2c1-1-r1c3)... continues with r1c9=1=r1c7

with

r1c1-5-r8c1=5=r8c9=3=r9c7. Together these nicely force r1c7<>3, which reduces this Extreme puzzle to Singletons.

The first "chain" is pretty messy; I'm wondering if anyone can find a more elegant, 1 or 2 step solution?

Cheers...

- drac

[edit]

Shoot, hit Submit instead of Preview... cleaned up mistakes. Also adding note that the forcing net starting from r1c1, if extended a bit, cancels out other value s(such as r5c3<>8 and, more obviously r4c7<>3), but I left that out. It's messey enuf and these are not needed to crack the puzzle.