Doppelgänger Warm-up
(Eingestellt am 3. Dezember 2025, 06:47 Uhr von Andrewsarchus)
An approachable Doppelgänger puzzle.
Rules:
- Doppelgänger Sudoku:
- Fill each row, coloum, and box in the main grid with digits from 0-9 without repeats.
- Every row, column, and 3x3 box in the main grid must contain a 0, and must therefore omit one of the digits from 1-9.
- Each digit from 1-9 is missing from exactly one row, one column, and one box.
- For each 0, the digit missing in its row, column, and box must be three distinct digits.
- Three auxiliary grids are provided for recording the missing digits.
- The 9x1 strip below the main grid records the digit missing in the corresponding column of the main grid.
- The 1x9 strip to the right of the main grid records the digit missing from the corresponding row of the main grid.
- The 3x3 box in the lower right records the digit missing from the corresponding box of the main grid.
- Thermometers:
- Digits along a thermometer strictly increase from bulb to tip.
Play Online:
sudokupad: Doppelgänger Warm-up
Lösungscode: column 5 (main grid only)
Kommentare
am 6. März 2026, 07:39 Uhr von wisty
lovely puzzle! thank you so much for setting and thank you orchidev for the recommendation! i find it hard to remember which sudoku works and which doesn't in these kinds of puzzles, but it's very smooth and nice logic overall
am 5. März 2026, 07:56 Uhr von orchidev
I loved this so much. I'm new to puzzles and this was really smooth, so cool the way it guides you through everything
am 7. Februar 2026, 08:03 Uhr von sme
How can I get help if I am stuck? without spoiling anything when asking the question? I end up very soon with two nines in a column and it seems I am not understanding the ruleset correctly. [...] I figured out the problem. Initially I thought the 3x3 box in the lower right corner would correspond to the zero that is at this position in the grid, but it corresponds to the box itself. an example would probably have helped beginners with this variant.
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You can ask in a hidden comment. You cannot see other people's hidden comments until you submit a solution code, but you can always see your own hidden comments, along with my replies.
If you are on the CtC discord server, you can also DM me there, and I'd even be able to help you in a voice-chat if you wish.
--Andrewsarchus
Thank you!
am 9. Dezember 2025, 12:42 Uhr von valacd
Felt very approachable. A great way to learn about doppelgänger puzzles (I got stuck in a very difficult one and figured I should try an easier one first), this puzzle taught me the tricks of a doppelgänger sudoku. Thanks a lot!
am 5. Dezember 2025, 18:02 Uhr von teuthida
It actually felt like a approachable Doppelgänger, thank you for setting and sharing!
am 4. Dezember 2025, 16:12 Uhr von bodemeister
Nice 8-minute run!
am 4. Dezember 2025, 06:47 Uhr von Playmaker6174
To be honest, "approachable Doppelgänger sudoku" sounded like a fever dream to me at first and after solving this one, it still kinda is (lol) but this one was certainly much easier than most of the puzzle using such concept I'd solved x)
I like the fact that this puzzle still left enough room for solvers to exercise the basic scanning with the concept and didn't try to overcomplicate or trivialize that task too much.
am 4. Dezember 2025, 01:30 Uhr von johnreid
Good fun, thanks!
am 3. Dezember 2025, 20:32 Uhr von dzamie
Dunno what people are complaining about, this is very approachable for a mildly complex variant like Doppelganger. The 9-length thermos provide an excellent starting point (the extra box basically starts solved). While some knowledge of how the extra box and extra row/column values interact is helpful, I don't think it's necessary.
Plus, the puzzle makes good use of the "a 0 replaces a different number for its row/col/box" rule. It's easy to forget, and in my solve, I managed to get a lot of the puzzle filled before absolutely needing to use it - this makes the most complex part of a Doppelganger relatively simple compared to other puzzles with the variant.
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lol - only VitP was actually complaining. The other comments are making fun of VitP's assertions. :-)
--Andrewsarchus
am 3. Dezember 2025, 20:07 Uhr von TVDK
THIS puzzle is a LEVEL 2 despite it being an ENTIRELY NON-INTUITIVE variant. As a FIRST solve of this variant still took less than 15 MINUTES. This INTRACTABLE puzzle was VERY NICE to solv- I mean- BIFURCATE.
am 3. Dezember 2025, 19:46 Uhr von Black_Doom
An EXTENSIVE research showed that a sudoku EXPERT needs ONLY 14 minutes of bifurcation to complete this SLIGHTLY less than COMPLETELY intractable puzzle that utilizes an ENTIRELY non-intuitive variant.
am 3. Dezember 2025, 19:22 Uhr von aqjhs
"approachable doppelgänger" = this.
why?
because:
- it uses the well established clue type that thermos are in a straight forward manner.
- features the logic of the doppelgänger setting in a non trivial and interesting way.
- allows for a solve path that increasingly involves that doppelgänger logic.
QED.
am 3. Dezember 2025, 16:51 Uhr von VitP
translation:
"approachable doppelganger" =
"slightly less than completely intractable"
why?
because:
- ordinary sudoku patterns are almost completely useless
- the variant is entirely non-intuitive, and does not correlate to any common variant
- absent any existing foundation, hours of bifurcation will be required, just to learn the basic patterns
-
am 3. Dezember 2025, 09:45 Uhr von SennyK
If you are not familiar with Doppelgänger, this is a perfect puzzle to start your adventrue with this fun sudoku type, really approachable!
am 3. Dezember 2025, 09:41 Uhr von Piatato
Smooth!
