[This puzzle comes from the 2022 US Sudoku Grand Prix round. This Killer Sudoku was one of my favorite constructions even though I don’t write the style too often. I wanted to get a chain of “last-digit eight” clues into a loop in the grid, and managed to find cage sizes that made good use of 8, 18, 28, and 38 values in this grid. While a few given digits were needed to seed the solving path, that did not diminish the unique “eight” theme visually or logically.]

PDF

or solve online (using our beta test of Penpa-Edit tools)

Theme: Eight Ouroboros

Author/Opus: This is the 442nd puzzle from Thomas Snyder, aka Dr. Sudoku.

Rules: Standard Sudoku rules. Also, the sum of the digits in each cage must equal the value given in the upper-left corner of that cage. Digits cannot repeat inside a cage.

Estimated Difficulty: 3.5 stars

Solution: PDF

Note: Follow this link for more Killer Sudoku and this link for classic Sudoku. More Killer Sudoku puzzles can be found in Killer Sudoku by Serkan Yürekli.

[This puzzle comes from the 2022 US Sudoku Grand Prix round. This variation again uses a double eights theme, both with two large eight shapes and a pair of given eights. I tried to have several different kinds of arrows used across the two eights, with a key question of should an eight be the sum of one or more of the arrows.]

PDF

or solve online (using our beta test of Penpa-Edit tools)

Theme: Double Eights

Author/Opus: This is the 441st puzzle from Thomas Snyder, aka Dr. Sudoku.

Rules: Standard Arrow Sudoku rules.

Estimated Difficulty: 3 stars

Solution: PDF

Note: Follow this link for more Arrow Sudoku. If you are new to this puzzle type, here are our easiest Arrow Sudoku to get started on. More Arrow Sudoku puzzles can be found in The Art of Sudoku 2 and Masterpiece Sudoku Mix 3.

[This puzzle comes from the 2022 US Sudoku Grand Prix round. Shape Sudoku is a variation I created many years ago where careful assignment of the givens to each of the shapes can lead to fun and narrow solving paths, so I really enjoy setting these kinds of puzzles. I had one big idea for the “eight” theme which you’ll certainly see while working through to the solution.]

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to alternate between Sudoku number entry mode and a shading mode to manage the shape inventory.)

Theme: Big Eight

Author/Opus: This is the 436th puzzle from Thomas Snyder, aka Dr. Sudoku.

Rules: Standard Shape Sudoku rules.

Estimated Difficulty: 4 stars

Solution: PDF

Note: Follow this link for other Shape Sudoku. More Shape Sudoku are in Masterpiece Sudoku Mix 8.

Continuing another long-running tradition, we have a new Kurotto puzzle from Prasanna Seshadri marking his 32nd birthday.

(view directly for a larger image)

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or solve online (using our beta test of Penpa-Edit tools)

Theme: 32 on 3/2/23

Author/Opus: This is the 250th puzzle from our contributing puzzlemaster Prasanna Seshadri.

Rules: Standard Kurotto rules. Also, numbers outside the grid show the number of separate shaded cells visible in that direction. A segment of length N in a given direction is taken as a building of height N. Buildings of height N block the view of all buildings behind them of equal or lesser height.

See also this example:

Difficulty: 4.5 stars

Time Standards (highlight to view): Grandmaster = 10:00, Master = 18:00, Expert = 36:00

Solution: To be added by next Sunday.

Note: Follow this link for classic Kurotto puzzles and this link for variations on Kurotto puzzles. If you are new to this puzzle type, here are our easiest Kurotto to get started on. More Kurotto puzzles can be found in the ebook Kurotto by Prasanna Seshadri.

See these earlier posts 1, 2, and 3 for the other Microsoft Puzzle Hunt challenges

Puzzle PDF

Author/Opus: This is the 433rd puzzle from Thomas Snyder, aka Dr. Sudoku.

Hints:
1. How do I get started? Pbafvqre gur fvatyr pryy ahzorerq fdhnerf dhvgr pnershyyl gb uryc svther bhg jung xvaq bs chmmyr guvf vf.
2. How do I solve this? Guvf vf n UVQNGB chmmyr jvgu ahzrevpny pbafgenvagf nf va n GbzGbz/Pnyphqbxh npebff pryyf. Sbe rknzcyr, gur 8÷ pntr pbagnvaf n 3 naq 24 (nf 24/3 = 8).
3. How do I get a final answer? Gur sbhe ? fdhnerf pbagnva gur inyhrf 46, 73, 85, naq 97 va fbzr beqre. Ohg gurfr inyhrf jba’g or nf vzcbegnag gb svavfu gur chmmyr nf gur cngu gb trg guebhtu gurz.

Solution: PDF

Answer String: Enter the final answer (a word or phrase) in ALL CAPITAL LETTERS without spaces to confirm. There may be intermediate answer phrases that are not the final answer; our answer checker is not able to send the message “Keep going” like the Microsoft Hunt solving software does so if you do not see what you expect, treat it like “Keep going” and potentially send an email to us or watch out for hints.

See these earlier posts 1, 2 for the other Microsoft Puzzle Hunt challenges

Puzzle PDF

Author/Opus: This is the 432nd puzzle from Thomas Snyder, aka Dr. Sudoku.

Hints (in rot13):
1. How do I get started? Gurfr ner bcrengvbayrff GbzGbz/XraXra chmmyrf, rnpu jvgu n havdhr vagrtre frg gnxvat svir inyhrf sebz 1-25 naq ab inyhr funerq npebff tevqf.
2. I’m stumped. How do I break into the puzzles? Znal pyhrf ner cynlshyyl qrprcgvir. 49 qbrf ybbx yvxr 7 gvzrf 7 gvzrf 1. Ohg vg pna nyfb or bgure fhzf yvxr 2K cyhf 2K cyhf L. Nyy guerr 49 pntrf va gurfr nafjref unir n ercrngrq ahzore. Vg znl nyfb uryc gb xabj gur bcrengvbaf sebz yrsg gb evtug va gur frpbaq ebjf ner {+, +, ×}, {+, ×, +}, {+, ×, -}, {-, +, ×}, naq {÷, +, -} va fbzr beqrevat bs gur tevqf.
3. How do I get a final answer? Juvyr gur tevqf ner tvira va {1,?,?,?,?} gb {5,?,?,?,?} beqre — jryy {1,7,8,14,17} gb {5,9,10,13,22} beqre — fbzrguvat ryfr va gur tevqf jvyy freir nf n orggre jnl gb svaq n bar-gb-svir beqrevat urer. Ybbx ng gur fnzr cbfvgvbaf jura ernqvat npebff tevqf ng gur raq gb trg n urycshy vafgehpgvba.

Solution: PDF

Answer String: Enter the final answer (a word or phrase) in ALL CAPITAL LETTERS without spaces to confirm. There may be intermediate answer phrases that are not the final answer; our answer checker is not able to send the message “Keep going” like the Microsoft Hunt solving software does so if you do not see what you expect, treat it like “Keep going” and potentially send an email to us or watch out for hints.

Puzzle PDF

Author/Opus: This is the 431st puzzle from Thomas Snyder, aka Dr. Sudoku.

Hints: (in rot13):
1. What are these strange puzzle types? Gurl’er glcrf bs ybtvp chmmyrf. Vs lbh frnepu sbe gurve anzrf ba guvf fvgr, gurer ner qrfpevcgvbaf, ubj gb fbyir thvqrf, naq rira ivqrbf.
2. How do I get started? Frira chmmyr glcrf jvgu whfg fvk tevqf? Lbh’yy svefg jnag gb svther bhg ubj rnpu tevq pna havdhryl fbyir nf whfg bar bs gubfr chmmyr glcrf, naq guebhtu fbyivat gur chmmyr vqragvsl gur ? inyhrf juvpu, va nyy pnfrf, ner abg arrqrq gb svaq gur fbyhgvba rkprcg sbe gur snpg gurl ner n pyhr pryy naq va fbzr fglyrf pnaabg or funqrq bire be orybat jvgu nabgure pyhr va na vfynaq/erpgnatyr.
3. How do I figure out which puzzle is which type? Gur tevqf jvgu gur srjrfg pyhrf ner Ahevxnor naq Fuvxnxh naq gur tevq jvgu gur zbfg pyhrf vf n Svyybzvab. Gur erznvavat guerr ner fcyvg npebff Pnir, Xhebznfh, naq Xhebggb. N xrl ybtvpny qrqhpgvba sbe Pnir vf gung lbh pna arire svyy va n purpxreobneq yvxr 2k2 cnggrea bs oynpx naq juvgr fdhnerf (be ryfr lbh jvyy ivbyngr gur pbaarpgvivgl ehyrf). Fb sbphf ba fbzr bs gur 2 pyhrf jvgu qvntbanyyl nqwnprag arvtuobef gb vqragvsl juvpu chmmyr zhfg or gur Pnir.
4. Which puzzle is which type? Sebz hccre yrsg gb ybjre evtug, gur chmmyr glcrf ner: Ahevxnor, Xhebggb; Xhebznfh, Pnir; Svyybzvab; Fuvxnxh.
5. How do I solve the bottom one on the left? Gur obggbz bar ba gur yrsg vf n Svyybzvab chmmyr. Vg znl or n irel uneq chmmyr gb fbyir hagvy lbh erpbtavmr gur tvira pyhrf nyernql nppbhag sbe ng yrnfg 30 (fvk svirf) + 30 (svir fvkrf) + 21 (guerr friraf) pryyf jbegu bs cbylbzvab tebhcf.
6. How do I get a final answer? Gur dhrfgvba znexf va gur qvssrerag tevqf jvyy fgnaq sbe {1,1,6}, {1,2,3,4}, {2,2,3,4}, {2,3,3,5}, {3,3,4,6}, naq {5,6,6,7} juvpu znl uryc vs lbh unir whfg n pbhcyr yrsg hafbyirq. Hfr gurfr inyhrf gb perngr gur 7gu zvffvat chmmyr, gura fbyir vg.

Solution: PDF

Answer String: Enter the final answer (a word or phrase) in ALL CAPITAL LETTERS without spaces to confirm. There may be intermediate answer phrases that are not the final answer; our answer checker is not able to send the message “Keep going” like the Microsoft Hunt solving software does so if you do not see what you expect, treat it like “Keep going” and potentially send an email to us or watch out for hints.

[Note: The remaining two Microsoft Puzzle Hunt puzzles will be released on upcoming future Sundays (starting Jan 29) since these are involved puzzles to solve and harder than our usual weekday content.]

[More comments about the site below; for now, here is the first of four puzzles that I wrote for last year’s Microsoft Puzzle Hunt. Our “Binary Earth” round had paired puzzles that would look similar with a “large thing” and a set of “small things” to look at. This is the easiest puzzle of the set, entitled EXPLORER. Just as at the Microsoft Puzzle Hunt, it is presented solely as a PDF with no specific instructions. I will add hints each day as I also release the other 3 puzzles I wrote for that Hunt this week.]

Puzzle PDF

Author/Opus: This is the 430th puzzle from Thomas Snyder, aka Dr. Sudoku.

Hints (in rot13):
1. What is this puzzle? Gur zrffntr vf qrfpevovat n “Zvarfjrrcre (Cragbzvab)” chmmyr naq gur hahfhny sbeznggvat jvyy or vzcbegnag nsgre fbyivat gung chmmyr (ohg abg orsber).
2. How do I get started? Orpnhfr cragbzvabrf unir znal pbaarpgrq pryyf, fbzr bs gur zbfg xrl pyhrf gb ybbx ng ner gur 1’f va qvssrerag ertvbaf bs gur tevq nf lbh pbafvqre funcrf. Fbzr bs gur cragbzvabrf ng gur gbc ner gur Y, C, naq M juvyr fbzr bs gur cragbzvabrf ng gur obggbz ner gur V, A, naq I.
3. I finished the first part. What now? Rnpu cragbzvab unf n ynory, naq gung zvtug uryc lbh xabj jurer gb ybbx gb svaq bhg jung gb qb ng gur raq.
4. How do I get a final answer? Ernq gur yrggref haqre gur cragbzvab ynoryf gb trg n 12-yrggre vafgehpgvba, gura sbyybj gung vafgehpgvba jvgu gur cragbzvabrf, znxvat ab bgure punatrf, gb erirny gur nafjre.

Solution: PDF

Answer String: Enter the final answer (a word or phrase) in ALL CAPITAL LETTERS without spaces to confirm. There may be intermediate answer phrases that are not the final answer; our answer checker is not able to send the message “Keep going” like the Microsoft Hunt solving software does so if you do not see what you expect, treat it like “Keep going” and potentially send an email to us or watch out for hints.

[Note: I had a very busy weekend, including some mental health care which took me offline completely for 4 days, so have not reformatted the puzzles for this week yet or made the second “Smashing the Sudoku” video either. Amazingly, those busy weekends did not include full completion of the USPC or any participation in the MIT Mystery Hunt so things must be pretty serious for me right now. Reflecting on some of the comments from my post last Thursday, I do not want this site to go completely dark during my sabbatical year, but it may be less predictable when content gets added until we have our other puzzlemasters able to do web tasks more. That said, I also don’t think we need to release more free web puzzles without a new platform that can really grow our audience. Our planning for 2023+ has kicked off in a new GMPuzzles Discord channel that we will open up to authors/top fans soon.]

(view directly for a larger image)

PDF

or solve online (using our beta test of Penpa-Edit tools)

Theme: Cross the Streams

Author/Opus: This is the 249th puzzle from our contributing puzzlemaster Prasanna Seshadri.

Rules: Standard Kakuro Rules. Also, some cells may remain empty but empty cells cannot share an edge with other empty cells.

Difficulty: 5 stars

Time Standards (highlight to view): Grandmaster = 15:30, Master = 20:00, Expert = 40:00

Solution: PDF and solving video.

Note: Follow this link for other Kakuro puzzles. More Kakuro puzzles can be found in Kakuro and Variations by Serkan Yürekli and in The Art of Puzzles 2.

PDF

or solve online (using our beta test of Penpa-Edit tools in Yajilin mode allowing line drawing and cell shading/unmarking; hitting tab can alternate to separate shading and edge drawing modes).

Theme: 2 and 3

Author/Opus: This is the 387th puzzle from our managing editor Serkan Yürekli.

Rules: Locate some automobiles in the grid having size 1×2 or 1×3. Each number in the grid should be part of an automobile, indicating the number of unoccupied cells the automobile can move to by traveling along its longest axis, stopped only by an edge of the grid or another automobile. No more than one number can be in an automobile. (Unlike other variations of this puzzle, there are no extra automobiles without numbers here.)

Also, see this example:

Difficulty: 3.5 stars

Time Standards (highlight to view): Grandmaster = 5:00, Master = 8:00, Expert = 16:00

Solution: PDF and solving video.

Note: Follow this link for more Parking Lot puzzles.