Case opened on LinkedIn Tango #632: 6×6 Tango grid, 9 preset cells, 4 sign constraints. The completed grid holds 18 suns and 18 moons across the 6×6 grid. Evidence chain: 27 deduced placements after givens.
Forensic read: only one symbol still valid (12); two matching symbols sandwich this cell (6); the no-three-in-a-row rule blocks a repeat (4); column balance closes the line (3); row balance forces the last symbol (2). × pairs dominate this board — opposite signs force alternating symbols and quickly eliminate one option per linked cell. Cross-check every = and × against filled cells — a broken pair is the fastest way to spot a wrong symbol.
Early exhibits (R1C2 → Sun (column balance closes the line); R1C4 → Sun (two matching symbols sandwich this cell); R2C1 → Sun (row balance forces the last symbol)) tie givens to sign constraints. Mid-case placements (R4C1 = Moon, R4C3 = Sun) confirm the propagation theory. Closing exhibits (R6C5 → Sun and R6C6 → Sun) complete the 6×6 grid without violating the no-three rule.
Balance audit: Every row and column holds exactly 3 suns and 3 moons (row 1: 3 suns, 3 moons; row 2: 3 suns, 3 moons; row 3: 3 suns, 3 moons; row 4: 3 suns, 3 moons; row 5: 3 suns, 3 moons; row 6: 3 suns, 3 moons). No row or column exceeds 3 of either symbol in the solution.
Constraint verification: 1 equal signs require matching neighbors; 3 opposite signs require different symbols. A single broken edge means the grid fails even if row balance looks correct.
No-three rule pass: scan every row and column for three consecutive suns or moons — none appear in the completed grid. Sandwich cases (sun-moon-sun patterns around a filled pair) often force the middle cell and show up as two matching symbols sandwich this cell deductions on boards like this.
Verdict: consistent 6×6 Tango solution. 18 suns and 18 moons across the 6×6 grid. Case closed — 27 deduced cells, zero rule violations.