Contest Puzzle: Linking 200 Cells by Prasanna Seshadri

Prasanna is celebrating two milestones this week and we will have two special large puzzles. The first one here recognizes Prasanna’s 200th submission on GMPuzzles, and combines three of the styles where Prasanna has written books for our e-store.

Puzzle by Prasanna Seshadri

(view directly for a larger image)

PDF

or solve online (using our beta test of Penpa-Edit tools; while solution checking is not enabled, if you are comfortable with the different tool selection options you should be able to fully solve the puzzle in this mode too.)

Theme: Linking 200 cells

Author/Opus: This is the 200th puzzle from our contributing puzzlemaster Prasanna Seshadri.

Rules:

Grids 1-2: Follow regular LITS rules. Between the two LITS grids, the corresponding white cells can never both be shaded, while the corresponding gray cells must be identical in the three 200-shaped regions.

Use the LITS solutions and your ingenuity to discover the needed constraints for Grids 3-4. For Grid 3, you will find that some gray circles must change color to white or black.

Grid 3: Follow regular Balance Loop rules. Additionally, the loop must cross itself if it passes through a gray circle. The loop must go straight throught the gray circle both times; in one direction the path behaves as if the circle is white with equal loop lengths, and in the other direction the path behaves as if the circle is black with unequal loop lengths. It is not required that the loop pass through all of the gray circles (but it must pass through all white and black circles). (See also the image below.)

Grid 4: Follow regular Yajilin rules.

When taken together, the grids yield a short final answer! Send this (less than five character) string to hiddencontest at gmpuzzles dot com by March 14th, 2021 to be eligible to win an e-book by Prasanna Seshadri. The contest is now closed and results summarized here.

Difficulty: 5 stars?

Solution: PDF

Balance Loop (Star Battle) by Serkan Yürekli

Balance Loop (Star Battle) by Serkan Yürekli

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to shift between shading mode, shape (star) placing mode, and the linex mode where left click+drag draws lines and right click marks X’s)

Theme: Only 4 You

Author/Opus: This is the 317th puzzle from our managing editor Serkan Yürekli.

Rules: (Standard Balance Loop rules.) Also, each row and column must contain exactly two stars. Stars cannot be placed in adjacent cells that share an edge or corner, and all stars must be on empty cells not used by the loop.

Difficulty: 4 stars

Time Standards (highlight to view): Grandmaster = 7:30, Master = 13:15, Expert = 26:30

Solution: PDF; a solution video is also available here.

Note: Follow this link for other Balance Loop puzzles. If you are new to this puzzle type, here are our easiest Balance Loop Puzzles to get started on. More Balance Loops can be found in our beginner-friendly collection Intro to GMPuzzles by Serkan Yürekli and in Balance Loop by Prasanna Seshadri and Murat Can Tonta.

Balance Loop (All Cells) by Murat Can Tonta

Balance Loop by Murat Can Tonta

PDF

or solve online (using our beta test of Penpa-Edit tools in linex mode where left click+drag draws lines and right click marks X’s)

Theme: Antisymmetry

Author/Opus: This is the 190th puzzle from our contributing puzzlemaster Murat Can Tonta.

Rules: Standard Balance Loop rules. Also, all cells must be visited by the loop.

Difficulty: 2.5 stars

Time Standards (highlight to view): Grandmaster = 2:15, Master = 3:15, Expert = 6:30

Solution: PDF; a solution video is also available here.

Note: Follow this link for other Balance Loop puzzles. If you are new to this puzzle type, here are our easiest Balance Loop Puzzles to get started on. More Balance Loops can be found in our beginner-friendly collection Intro to GMPuzzles by Serkan Yürekli and in Balance Loop by Prasanna Seshadri and Murat Can Tonta.

Balance Loop (Star Battle) by Serkan Yürekli

Balance Loop by Serkan Yürekli

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to shift between shading mode, shape (star) placing mode, and the linex mode where left click+drag draws lines and right click marks X’s)

Theme: White Hole

Author/Opus: This is the 306th puzzle from our managing editor Serkan Yürekli.

Rules: Standard Balance Loop rules. Also, each row and column must contain exactly two stars. Stars cannot be placed in adjacent cells that share an edge or corner, and all stars must be on empty cells not used by the loop.

Difficulty: 4.5 stars

Time Standards (highlight to view): Grandmaster = 13:00, Master = 18:30, Expert = 37:00

Solution: PDF; a solution video is also available here.

Note: Follow this link for other Balance Loop puzzles. If you are new to this puzzle type, here are our easiest Balance Loop Puzzles to get started on. More Balance Loops can be found in our beginner-friendly collection Intro to GMPuzzles by Serkan Yürekli and in Balance Loop by Prasanna Seshadri and Murat Can Tonta.

Balance Loop (Skyscrapers) by Murat Can Tonta

Balance Loop by Murat Can Tonta

PDF

or solve online (using our beta test of Penpa-Edit tools in linex mode where left click+drag draws lines and right click marks X’s)

Theme: Pairs

Author/Opus: This is the 184th puzzle from our contributing puzzlemaster Murat Can Tonta.

Rules: Standard Balance Loop rules. Also, numbers outside the grid show the number of separate loop segments 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.

Also, see this example:

Balance Loop by Serkan Yürekli

Difficulty: 3.5 stars

Time Standards (highlight to view): Grandmaster = 4:30, Master = 7:00, Expert = 14:00

Solution: PDF; a solution video is also available here.

Note: Follow this link for other Balance Loop puzzles. If you are new to this puzzle type, here are our easiest Balance Loop Puzzles to get started on. More Balance Loops can be found in our beginner-friendly collection Intro to GMPuzzles by Serkan Yürekli and in Balance Loop by Prasanna Seshadri and Murat Can Tonta.

4-Way Loop by Serkan Yürekli

4-Way Loop by Serkan Yürekli

(View image directly for larger form.)

PDF

or solve online (using our beta test of Penpa-Edit tools in yajilin mode where left click shades squares, left click+drag draws lines and right click marks X’s; note that the default puzzle info is too long — even for an url shortener — so copy and paste all the text in this file into the “Load” option in the upper-right of the penpa-edit interface to access.)

Theme: Clue Symmetry and Logic (for TheSubro)

Author/Opus: This is the 158th puzzle from our contributing puzzlemaster Serkan Yürekli.

Rules: This puzzle combines four loop varieties commonly featured at GMPuzzles: Balance Loop (upper left), Yajilin (upper right), Castle Wall (lower left), and Masyu (lower right).

Draw a single, non-intersecting loop throughout all four quadrants. The loop may enter and exit the different quadrants as many times as needed.

The standard rules for each puzzle type are true for each quadrant, with these additional considerations:

Balance Loop: Use the entire length of segments (including parts of the segments that extend into an adjacent quadrant) when determining the balanced/unbalanced status of a circle clue.

Yajilin: The arrow clues refer only to shaded cells within the Yajilin quadrant. The loop must occupy all cells adjacent to a shaded cell, even in an adjacent quadrant.

Castle Wall: Number clues only apply within the grid and DO NOT include any line segments that cross the bold border with another grid or any segments in other quadrants. (Another way to say this is that the Castle Wall clues refer to the number of thin lines crossed in the lower-left quadrant only.)

Masyu: Normal rules apply for white and black circles, but the path satisfying these rules can extend into an adjacent quadrant. (For example, a white circle can be passed through crossing a quadrant edge, provided it turns immediately on one side of the circle whether the turn is in the Masyu quadrant or in another quadrant.)

Answer String: Enter the length in cells of the horizontal loop segments from left to right in the marked rows, starting at the top. If the loop only has vertical segments in the marked row, enter 0. Separate each row’s entry with a comma.

Solution: PDF

Time Standards (highlight to view): Grandmaster = 18:00, Master = 35:00, Expert = 1:10:00

Masyu or Balance Loop? by Carl Worth

Masyu/Balance Loop by Carl Worth

PDF

or solve online (using our beta test of Penpa-Edit tools in linex mode where left click+drag draws lines and right click marks X’s)

Theme: Almost Antisymmetric

Author/Opus: This is the 21st puzzle from our contributing puzzlemaster Carl Worth.

Rules: Combination of Masyu and Balance Loop rules. In each horizontal row, all the circles obey the same rules, which are Masyu rules or Balance Loop rules. You must determine what rule applies to each row in order to form the single loop that solves the puzzle.

Answer String: Enter the length in cells of the horizontal loop segments from left to right in the marked rows, starting at the top. If the loop only has vertical segments in the marked row, enter 0. Separate each row’s entry with a comma.

Time Standards (highlight to view): Grandmaster = 7:00, Master = 9:30, Expert = 19:00

Solution: PDF; a solution video is available here.

Note: Follow this link for other Masyu and Balance Loop puzzles.