A Clean Solve on Expert Challenge 139

The puzzle

Expert Challenge 139 (神 Expert tier) draws on the full technique library — Naked Single, Hidden Single, Naked Pair, Hidden Pair, Pointing Pair, and X-Wing all show up somewhere in its solve path. It is not a puzzle that gives in to guessing.

The full solve

Step through DragonQi's real, unedited move history below — 107 seconds, zero mistakes, every entry tagged with the actual technique that explains it, plus a plain-English caption for why each move works.