Puzzle Description Suppressed:Click below to view spoilers

#1: Gator (gator) on Apr 19, 2022 [HINT]

(Not sure what is required here, but these are my advanced steps so far.)

After initial LL about half of puzzle will be solved. EL on C3 makes R1-7C3 dots.

EL on C4 makes R1-6C4 dots.

EL on C31 makes R5C31 a dot. LL.

EL on R1 makes R1C5,28-9 dots.

EL on C32 makes R8C32 a dot. LL.

EL on R17 makes R17C11-4,28-9 dots. LL.

EL on C26 makes R13C26 a dot. LL.

IEL on C25 makes R13C25 a dot. LL.

Two way logic in C26 makes R10C25 always black. LL.

Two way logic on the 2 clue in R15 forces both R13C5 and R14C5 to be dots.

EL on the 3 clue in R1 will cause a contradiction in C5, so R1C6 is a dot.

EL on the 4 clue in R2 will cause a contradiction in C7, so R2C5 is a dot.

EL on the 3 clue in R1 with deep lookahead will cause a contradiction, so R1C7 is a dot.

R10C4 is always a dot no matter where the 3 clue in C3 is placed. Likewise R7C4 is also always a dot.

I'm going to have to stop here for now.

Anyway it looks delicious!

Comment Suppressed:Click below to view spoilers

There is definitely some advanced work in this one Gator, but I solved it on paper before publishing so I'm sure it's possible without any guessing! The first draft was so much worse with multiple rows of edge logic in the middle- painful! Let me know if you get stuck.

Great puzzle, not easy, had to use all my tools to include interior edge logic, almost "saved" it to finish later, but I know I rarely get back to them, so I checked the comments and saw that people are finishing it, so went back and dug in until I got it. Well worth the trip!

Continuing from where I left off.

With 4 move lookahead, if you place the 3 clue in R1 at R1C8-10, then it will cause C5 to be invalid. So R1C8 is a dot. With 3 move lookahead, R1C9 is also a dot. With 3 move lookahead, R1C10 is a dot. With 2 move lookahead, R1C11 is a dot.

R2C6 is a dot with EL. With 4 move lookahead, R2C7 is a dot. With 3 move lookahead, R2C8 is a dot. With 2 move lookahead, R2C9 is a dot.

With 2 move lookahead, R3C5 is a dot. EL on R3 makes R3C6-7 dots.

The 3 clue in C3 can only go in R8-10, R10-12, R12-14, or R13-15 without making C4 invalid. However, if it goes in R10-12 or R12-14, then C5 will be invalid. So this limits us to only R8-10 or R13-15 being valid options for the 3 clue. So R11-12C3 are dots. This now lets us make R11C4 a dot with EL.

If we place the 3 clue in C3 in R8-10, then R15C5 will be black. If we place the 3 clue in R13-15, then R12C5 will be black. Since C5 only has a 1 clue left and it has to be either at R12 or R15, this lets us dot R4-11C5.

EL on the 4 clue in C6 makes R4C6 a dot. We cannot go further down though since R8C6 could still possibly be a 1 clue.

With 3 move lookahead, R4C7 is a dot.

I know the puzzle image is screaming at me to place the 3 clue at R13-15C3, but the clues haven't forced me to do that yet.

I'm going to have to come back again later. (And if I am overlooking some obvious logic, please let me know.)

I enjoyed this puzzle. Thank you

Found to be solvable with deep lookahead by wombatilim.

I somehow missed Gator's hints before I started going through this one. I'm sure there's a fair bit of overlap but we didn't necessarily go after things in the same order.

C3: EL marks R1-7 white.
C4: EL marks R1-6 white.
R17: EL marks C11-12 white.
C32: Whichever way the 3 goes, R8-9 C29 are black. LL.
C29: Neither R1 nor R6 can be white, or it contradicts in C28.
C30: EL marks R16 white. LL.
R17: EL marks C25-29 white. LL.
R16: EL marks C29 white. LL.
C26: EL marks R13 white. LL.
C26: Whichever way the 5 goes, R7C25 is white.
C27: Whichever way the 5 goes, R2C26 is white.
R16: Whichever way the 2 goes, R13-14 C5 are white.
C25: if the blacks in R8-9 are the 2 clue, it causes a contradiction in R1, so R10C25 must be black. LL.

Deep lookahead R15: if the 2 in R15 goes into C3, then in 4 moves it will place a 1 in C5, which would complete the column. R1-11 C5 are white. LL.

C3: EL marks R11 white. Minimal LL.

C6: EL marks R1-4 white.
C7: EL marks R1-2 white.
R1: EL marks C8-9 white.

C6: If R3 or R4 is black, C6 is invalid in 2 moves. These squares are white.
C5: EL v.C8 can mark R5-6 white.
C6: EL can mark R5 white.
R2: EL marks C8-9 white.

Deep lookahead R1: If the 3 starts in C10 or C11, R4 is made invalid in 2-3 moves. R1 C10-11 are white.

Deep lookahead C6: If the 4 starts in R7, R8-10 C3-4 would need to be white for the first 3 in C7 to fit. This would place blacks in R13-14 C3 and R12-13 C4, followed by black in R12C5. However, blacks now need to go into both R12 and R15 in C3, which makes C3 invalid. Therefore R7C8 must be white. LL.

C6: Whether the 4 goes into R10 or R12, R12C3 will be white.

C11: If R11 is black, R7C10 will also need to be black, which makes C11 invalid. R11C11 must be white.

R14: If the black in C7 is part of the first 2, the 1 must be in C3, which makes the black in R10C7 the 1 in R10, so R12-14 would be black, completing that 2. So whether R14C7 is the 1 or part of the first 2, R14C8 is white.

Deep lookahead R2: If the 4 is placed in C10-13, the 3 in R3 is in C11-13, completing C12-13 and puts the 4 in C11 into R2-5, which completes that column as well. The 4 in C10 must now be in R4-7, but that adds an additional black into C11, which makes C11 invalid. Therefore R2C10 must be white.

R2: If the 4 is placed in C11-14, the 4 in C11 is placed in R2-5. This means the 3 in R3 must go into C12, completing that column. The 2s in R4-5 must then both go into C10, which is invalid. Therefore R2C11 is white.

C11: If the 4 is placed in R3-6, the 3 in R3 would need to go into C12. This means R5-6 would both need to put black in C10, which would place the 4 in C10 into R5-8. Doing this places another black into C11, which makes the column invalid. Therefore, R3C11 is white. Minimal LL.

Deep lookahead R3: The 5 can be placed in C12-16, C20-24, or C21-25 without a contradiction within 2 moves. If it is placed in C12-16, the 3 in R3 must be in C8-10, and the 4 in R2 must be in C12-15. This would complete C8-9 and C12-13, leaving the 4 in R7 with no way to finish. Therefore the 5 must be in one of the other two positions, and R3 C21-24 can be marked black. LL.

Deep lookahead R3: If the 3 is in C8-10, it makes R3 C12-19 and R4 C10-25 white. The 2 in R2 will need to be in C24-25. The only place the 4 in R2 could go that doesn’t cause a contradiction within 2 moves would be C13-16. Once again this will complete both C9 and C13, making R7 invalid. Therefore R3 C8-10 is white.

Deep lookahead R2: C24-25 are either both white or both black, based on how they interact with the 2 in R4. If they are both white, R3C25 will be black, and the 1 in R2 will be in either C20 or C27. The only way to fit the 1 in C20 is to have the 4 in C12-15 and the 2 in C17-18. This placement will require the use of the 3s in both R1 and R3, making C20 an invalid placement for the 1. This means the only viable position for the 1, regardless of whether R2 C24-25 are black, is in R2C27. Minimal LL.

Deep lookahead R7: If the 4 extends into C13, it marks R1-5 white in C12-13. The only viable placement for the 4 in R2 would be in C17-20. The 2 in C17 could not go into R1, because it would need to go back into R2 at C15, so instead it would place the 3 in R3 into C15-17. In 2 more moves we would need to place black in R5C13, which is invalid. Therefore the 4 in R7 needs to go into C9-10 instead. LL.

R13: The black in C11 is either the 1 or part of a 2. If it is the 1, the first 2 must go into C3-4. This makes the black in R10C7 the 1 in R10. If instead R13C11 is part of a 2, a black is placed in R10C10, which means the black in R10C7 is still the 1 in R10. Either way, R10 C3-4, C6, and C8 are all white.

LL to finish.

"C6: EL can mark R5 white.
Deep lookahead C6: If the 4 starts in R7, R8-10 C3-4 would need to be white for the first 3 in C7 to fit."

I'm not sure if I'm seeing this. Considering the 2s in R8-9 can go in earlier columns, I'm not seeing if this IEL works for me.

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