What changes on Medium?
Medium Space Sudoku starts with about a third of the squares filled in. That means a quick row scan won’t finish the puzzle on its own — you’ll need to combine rows, columns AND the 2×3 box rule to find each next space friend.
If Medium feels like a big jump, take a break and warm up on a couple of Easy puzzles first. The Space Sudoku page has the full rules and a friendly walk-through.
Three icon-spotting tricks
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Box scan
Pick a 2×3 box that already has four or five space friends. Look at the missing ones and check which empty square each can go into based on the row and column rules.
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Twin sweep
If two squares in the same row can only be a rocket or a comet, no other square in that row can be a rocket or a comet. That fact often unlocks a third icon somewhere else.
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Same icon squad
Tap any filled icon and the board lights up every other square with that icon. It’s a fast way to spot which rows or columns still need that space friend.
When you get stuck
- ✏️ Turn on Auto Notes for a clean candidate-map view
- 🔎 Tap Check — if you have a wrong icon, fix it before going further
- 💡 Tap Hint to reveal one square (it counts in your stats, but that’s fine)
- ↻ Tap Undo to step back if a placement turned out wrong
Ready for the next step?
When Medium Space Sudoku takes you under five minutes, try Hard Space Sudoku. Hard puzzles drop a few more givens and reward planning ahead.
Frequently asked questions
How long should Medium Space Sudoku take?
Most kids finish in 5 to 10 minutes. If it takes longer, that’s fine — use Notes and tap Check whenever you want to make sure you’re on track.
Can I switch back to Easy?
Of course — just tap the Easy tab at the top of the board. Your Medium puzzle saves automatically.
Why are there fewer given icons?
Fewer starting icons force you to use the box rule more. The board still has exactly one solution, but you have to combine all three rules to find it.
Try other sudoku games
Different look, same friendly logic. Pick a sibling puzzle to play next.