Official explanation
u/JamesBaxter_Horse
F - dots AND, lines XOR
Note: The puzzle is designed so the sequences work horizontally or vertically. Also because XOR is a self-inverse, the lines also work backwards, i.e. starting at the empty square, but the dots don’t.
Why we selected it: The comment identifies both rules and goes a step further by checking the pattern horizontally and vertically.
u/Liko81
F
The dots in the third panel of each row are the “intersection” or “and” join of the first two; if you see a dot in the same position in both of the first two panels, it should be in the third. The lines are an “XOR” join; if a line is in either the first or the second, but not both, then it should be in the third panel.
Why we selected it: This is the clearest step-by-step explanation of how the dots and lines follow different rules.
u/Confident-Classic-63
F – Add the lines from the first two figures together: where they overlap, they cancel each other out; where they are not present in both, they appear in the third figure. The dots work the opposite way: where they are present in the first two figures, they are also present in the third; where they are absent from both of the first two figures, they are also absent from the third.
Why we selected it: It explains the visual operation in everyday language, making the solution accessible without knowing the terms AND and XOR.
u/funtobedone
F
Vertically, delete lines in common. Keep dots in common.
Why we selected it: This concise comment shows that the answer can also be verified by reading the grid vertically.
