# Puzzles

Difficulties are marked according to the Logic Masters Germany scale. These are just my best guesses, so please let me know if you have a different opinion!

All OctoPuzzles links come with walkthroughs if you need help at any point. (Not all puzzles have OctoPuzzles links.)

## Sudoku

If you are new to puzzle-solving, you may want to read the rules of common sudoku variants. I also have recommendations for newbies.

### Fillomino Chaos Construction (5★)

Written on May 22, 2023.

CTC

Penpa

### Tepper (2★)

Written on May 8, 2023.

CTC

F-Puzzles

Penpa

Written on April 22, 2023.

CTC

F-Puzzles

### 6:13 (3★)

Written on April 16, 2023.

Cells a Knight’s move (in chess) apart may not contain the same digits.

CTC

OctoPuzzles

F-Puzzles

Penpa

### Conjoined (2★)

Published on April 4, 2023.

CTC

F-Puzzles

Penpa

### 9x9 Skyscraper Thermos (4★)

Written on March 23, 2023.

Penpa

### 6x6 Skyscraper Thermos (2★)

Written on March 22, 2023.

Penpa

### Minutia (1★)

Written on March 21, 2023.

CTC

F-Puzzles

### Pointy (3★)

Written on March 19, 2023.

CTC

F-Puzzles

### Wings (2★)

Written on March 18, 2023.

CTC

F-Puzzles

### Zoom (2★)

Written on March 13, 2023.

CTC

F-Puzzles

### Monster Without A Name (4★)

Written on March 11, 2023.

This puzzle is a chaos construction. Cages indicate the product of each region sum contained in a cage. For instance, if a 4-cell cage contained 1,2 in one region and 3,4 in another region, its total would be $(1+2)\times (3+4)=21$. Cages may be contained in one region, in which case, the total is just the sum of the cells. Digits may not repeat in a cage.

CTC

F-Puzzles

Penpa

### Cars (2★)

Written on March 5, 2023.

CTC

F-Puzzles

### Monster Cages (3★)

Written on March 4, 2023.

This puzzle is a chaos construction. Cages indicate the product of each region sum contained in a cage. For instance, if a 4-cell cage contained 3,5 in one region and 4,6 in another region, its total would be $(3+5)\times (4+6)=80$. Cages may be contained in one region, in which case, the total is just the sum of the cells. Digits may not repeat in a cage.

CTC

F-Puzzles

Penpa

### Intersections (2★)

Written on February 27, 2023.

CTC

F-Puzzles

Penpa

### Starry Sums (2★)

Written on February 21, 2023.

Shade a square in each row, column, and region such that each digit 1-9 is shaded once and no two shaded squares touch, not even diagonally. Digits outside the grid indicate the sum of the digits it sees before the shaded square.

CTC

F-Puzzles

Penpa

OctoPuzzles

### QT (1★)

Written on February 17, 2023.

CTC

F-Puzzles

OctoPuzzles

### X-Lines Sudoku (4★)

Written on February 14, 2023.

On an X-Line, if X is on the line then so must 10-X. Digits may repeat on a line, so 1159 would be a valid X-Line.

CTC

F-Puzzles

Penpa

### Class of ’23 (3★)

Written on February 11, 2023.

CTC

F-Puzzles

OctoPuzzles

Penpa

CTC

F-Puzzles

Penpa

### Stairs (2★)

Written on February 6, 2023.

CTC

F-Puzzles

Penpa

### Highway (2.5★)

Written on February 1, 2023.

CTC

F-Puzzles

Penpa

### Genome (2★)

Written on January 31, 2023.

CTC

F-Puzzles

Penpa

### Bird (3★)

Written on January 19, 2023.

CTC

F-Puzzles

Penpa

### Kakuro Sudoku (2★)

Written on January 11, 2023.

Each number in a shaded cell is either the sum of the two digits below or to the right of it (possibly both).

CTC

F-Puzzles

Penpa

### Equations (2★)

Written on January 7, 2023.

Digits in cells separated by +, x, and = signs form valid arithmetic operations. (All arithmetic operations involve only one-digit numbers.) Classic sudoku rules apply.

CTC

F-Puzzles

Penpa

### Uzumaki (1★)

Written on January 6, 2023.

CTC

F-Puzzles

Penpa

### Hooks and Swipes (1★)

Written on January 4, 2023.

CTC

F-Puzzles

Penpa

### Snowflake (1★)

Written on January 3, 2023.

CTC

F-Puzzles

Penpa

### Distant Neighbors (2★)

Written on January 2, 2022.

Every number must be adjacent to at least one number 4 away from it. For example, 4 must share a side with either a 8 or a 9 (possibly both).

CTC

F-Puzzles

Penpa

### Close Neighbors (1★)

Written on December 31, 2022. As featured on Cracking the Cryptic.

Every number must share a side with at least one other consecutive number. For example, 2 must share a side with either a 1 or a 3 (possibly both).

CTC

F-Puzzles

Penpa

### That’s What I Mean (2.5★)

Written on December 28, 2022.

Numbers in a blue circle are the arithmetic mean of its orthogonal neighbors.

CTC

F-Puzzles

### 7-Eleven (3★)

Written on December 8, 2022.

The digits orthogonally adjacent to a 7 must sum to 11.

CTC

F-Puzzles

### 5 (2★)

Written on December 3, 2022. As featured on Cracking the Cryptic.

The line is a German Whisper. As far as I know, F-Puzzles does not have an option to create a German Whisper, so it does not have any error checking. (Penpa does not either, and placing XV’s is annoying, so I opted to use F-Puzzles instead.)

CTC

F-Puzzles

### Alphabet Soup (5★)

Written on November 4, 2022. Warning: This puzzle is extremely hard.

This puzzle has some special rules: each thermo displayed in the right grid must be placed in a unique $3 \times 3$ subgrid on the left grid. Moreover, the position of each thermo must not change with respect to its subgrid (meaning no rotation or translation within the subgrid).

Also note that the answer check will only work when the right side is cleared of digits (though you, of course, may consider yourself finished at the time you place the last digit in the left side of the grid).

Penpa

An example puzzle is shown below.

Example (Penpa)

Hint 1
Exactly three 1’s are in the bottom row of their box. (The same holds true for any other digit, any other row, or any other column.)
Hint 2
You need to consider at most how many 1’s and how many 2’s can be in the bottom row in conjunction, according to the thermos. Then you need to ask how many there are, according to sudoku rules. (Use Hint 1 for the latter part!)

### X Marks the Spot (3★)

Written on October 28, 2022. Revised on February 26, 2022 in order to make the ending smoother.

Penpa

F-Puzzles

## Star Battle

In a star battle, some number of stars must be placed in every row, column, and region. No two stars may touch, even diagonally.

### Sandwich Stars (1★)

Written on February 4, 2023.

Two stars must be placed in every row and column. No two stars may touch, even diagonally.

Additionally, it must be possible to place some digits in cells without stars that signify the number of adjacent stars (diagonally adjacent cells count) and digits do not repeat in a row or column. Also, clues outside a row or column indicate the sum of the digits between the stars.

Cells with a circle must have a digit in them.

Determining where every digits goes is not part of the puzzle; it merely must be possible to place them. (In other words, the placement of the digits is not necessarily unique; only the placement of the stars must be.)

Penpa

### Latin Stars (1★)

Written on February 4, 2023.

Two stars must be placed in every row and column. No two stars may touch, even diagonally.

Additionally, it must be possible to place some digits in cells without stars that signify the number of adjacent stars (diagonally adjacent cells count) and digits do not repeat in a row or column.

Also, some digits are given as clues are outside each row and column. The first X squares in a row or column in the direction of a clue, where X is the first digit seen in that row or column (which is not necessarily in the first square of the row or column), must add to the indicated sum. (Any square without a digit does not contribute to the sum.)

Determining where these digits go is not part of the puzzle; it merely must be possible to place them. (In other words, the placement of the digits is not necessarily unique; only the placement of the stars must be.)

Penpa

### Star Battle 1 (1★)

Written on January 27, 2023.

Penpa

## Suguru

These aren’t actually vanilla Sugurus, they are Suguru Chaos (De)constructions, a puzzle genre that mathpesto has popularized. Typically the rules are to construct regions of size n with digits 1–n (where n is no greater than 9), and digits in a row/column cannot repeat. Regions cannot be orthogonally adjacent, though they may be diagonally adjacent.

### First Burn (5★)

Written on May 3, 2023.

Each line is either a Whisper or a Scream; the solver must determine which. Adjacent digits on a Whisper line differ by 5 or more. Adjacent digits on a Scream line differ by 2 or more, and furthermore, every digit on a Scream must be high (6789).

If two cells along the same Whisper line are not on an orthogonally connected path along the line, then they must not be in the same region. This rule does not apply for Scream lines.

CTC

OctoPuzzles

F-Puzzles

Penpa

### Silent Suguru (5★)

Written on April 24, 2023.

Adjacent digits on a German Whisper line differ by 5 or more. Two cells along the same German Whisper belong in the same region if and only if they are on an orthogonally connected path along the line.

CTC

OctoPuzzles

F-Puzzles

Penpa

1. This puzzle was changed from February 7, 2023 to make the puzzle look more like a heart. It had the pleasant side effect of improving the logic and getting rid of a 2-cell thermo :)↩︎