Puzzle Description Suppressed:Click below to view spoilers

#1: Kristen Vognild (kristen) on Feb 4, 2019 [SPOILER]

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I enjoyed it. Thank you. The top was hard but still logical.

That was really hard, but very satisfying, all logical.

Here's how I solved it, I think some of these steps are deep lookahead:
CL/LL
Deep EL 8 in R22:
* Note that top clues in C14-16, 18-20, 25-27 are 1-2-1, but R21 has no 1 clues.
* So if the 8 in R22 spans any of those triplets of columns, it forces a 1 into R23
* Thus R22 C12-18 are white
EL in R22 from the right: rightmost 2 cannot reach C37+, so C21 is black
EL leftmost 4 in R23: C12 is white
deep EL 4s in R23:
* Since C30-34 top clue is 1, black in R23 will make R22 white
* rightmost 4 in R23 cannot reach C32+ (partly due to the restriction on the rightmost 2 in R22 earlier)
* thus R22 C28-29 are black
LL
remembering restriction on rightmost 2 in R22 from earlier, R22 C32,35 are black
LL
2-way: 2 in C26 is in R21 or 23. Either way, the final 1 clue in C27 will be in R21 or R23, so the rest of C27 is white.
LL
Counting: by the column clues, C31 R22-23 has only 1, C36 R22-23 has only 1, and C33-34 have only 1 remaining each.
* In those columns, R22 must have 2 more (the 2 clues), and R23 must have 1 (the 1 clue).
* So there can only be 1 more black in C33-34 R21,24+.
* Thus C33-34 R21,31 are white
2-way: 4 in R29 is in C30 or C34. Either way, the 2 in R30 is C31-32.
LL
2-way: 2 in C19 is in R21 or 23. Either way, the final 1 clue in C18 is in R21 or R23, so the rest of C18 is white.
LL to finish

Solved it with no hints. Challenging! Thank you.

cute :)

Found to be solvable with moderate lookahead by wombatilim.

Initial line & color logic completes 88% with only black remaining.

R22: EL puts blacks in C22-26. LL.
C12: EL marks R23 white.

R22: If the 2nd 2 is in C36-37, it makes C39 invalid. This nudges the 8 over, and R22C21 is black. LL.

R23: EL marks C13 white.

R23: Wherever the 2nd 4 is placed, it puts at least 3 whites in R22. If it goes into C30-33 or C31-34, there won’t be enough room for all of the clues in R22. Remembering the restriction on the 2nd 2 in R22 would make C29-32 an invalid position as well. This marks R23 C28-29 black. LL.

R23: Remembering the restriction on the 2nd 2, we can mark C32 and C35 black. LL.

C12: However the 2 is placed, R25-26 C13 are black. LL.

R29: If the 4 is in C16-19, R30 is invalid, so R29 C32-33 are black. LL.

R30: If C34-35 are black, R29 is invalid. Minimal LL.

C26: Whether the first 2 goes into R21 or R23, C27 is completed. R22, R24, R26-27, and R32-34 C27 are white. LL.

C19: Whether the 2 goes into R21 or R32, C18 is completed. R24, R26-27, and R29-31 C18 are white.

R31: If the remaining 2 goes to C16-17, R29-30 C14 would need to be black, and R32C17 would need to be black. If the remaining 2 in R31 goes into C33-34, R29 C30-31 would need to be black, and R32C31 would need to be black. Either of these accounts for the remaining 1 in R32, so R32 C13, C15-16, and C30 are white. Minimal LL.

R30: If the 2nd 3 goes to C13, R29 is invalid.

LL to finish.

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