🧭 Expedition · this week
Echoes in the Icefall
★★★★★🧩 Killer · no givens
New expedition in
4d
4d
The weekly challenge. The board starts completely empty — not a single given digit. The constraints alone carry the whole solve. No clock, no pressure, and your progress follows you across devices. Chip away at it all week; finishing is the feat.
🧭Finish while it's live: dated weekly badge + 3000 bonus XP
- Normal sudoku rules apply: fill every row, column, and 3×3 box with 1–9.
- Along green lines, adjacent digits differ by at least 5.
- Cages sum to the small clue in their top-left corner; digits cannot repeat in a cage.
🏁 Finishers
Nobody has reached the summit yet. Be the first.