PDF

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

Theme: Logic

Rules: Hybrid of Nurikabe and Sashigane, originally created by Grant Fikes. Standard Nurikabe rules are in place for the “ocean” (connected and no 2×2 squares) but the island rules have changed as follows:
1. All islands must be L-shaped and one cell wide. Islands cannot share an edge.
2. An arrow clue points from an end of an island towards the bend in the middle.
3. A circle clue indicates the bend in the middle of an island; if a number is also present, this is the size of the island in cells.
4. An island can have 0, 1, or more of these clues given.

Also see this example and solution by Thomas Snyder:

Answer String: Enter the length in cells of each of the black segments (the unnumbered, connected “ocean”) from left to right for the marked rows, starting at the top. Separate each row’s entry from the next with a comma.

Time Standards (highlight to view): Grandmaster = 5:00, Master = 6:30, Expert = 13:00

Solution: PDF

Today’s surprise originally comes from Hans van Stippent, with some edits by me (Thomas Snyder) to increase the challenge and rewards of the solve. Together, we present this creative “Mystery Tapa” where all the clues (any value from 1-8) have been replaced with ?’s.

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to shift between shading mode and the composite Yajilin mode where left click marks cells, right click marks dots in cells or X’s on edges, left click+drag draws lines.)

Theme: Clueless?

Rules: Variation of Tapa rules. All clue numbers (1 and above) have been replaced with question marks.

Answer String: Enter the length in cells of each of the shaded segments from left to right for the marked rows, starting at the top. Separate each row entry from the next with a comma. A double-digit number should have both digits entered.

Solution: PDF

(view image directly for a larger format.)

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to shift between shading mode and the composite Yajilin mode where left click marks cells, right click marks dots in cells or X’s on edges, left click+drag draws lines.)

Theme: Group Think

Rules: Standard Tapa rules.

Answer String: Enter the length in cells of each of the shaded segments from left to right for the marked rows, starting at the top. Separate each row’s entry from the next with a comma. A double-digit number should have both digits entered.

Time Standards (highlight to view): Grandmaster = 2:15, Master = 4:30, Expert = 9:00

Solution: PDF

Editorial Note: If you have been enjoying Serkan’s puzzles, you may want to try SudokuCup 10 this weekend where he has provided all the sudoku puzzles. And daily Tapa puzzles continue to be at Logic Masters India for the Classic Tapa Contest. Serkan is indeed the Puzzle Robot.

PDF

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

This is a “Franken-Friday” puzzle variation.

Theme: Logical

Rules: Standard Cross the Streams rules, except that the puzzle uses an early number system that only has the concepts of “one” and “many”. All number clues greater than 1 are represented by a + symbol.

Answer String: Enter the length in cells of each of the black segments from top to bottom for the marked columns, going in order from A to B to C to D and separating each entry with a comma.

Time Standards (highlight to view): Grandmaster = 3:15, Master = 6:30, Expert = 13:00

Solution: PDF

Editorial Note: This variation was inspired by a puzzle on a recent Tapa Variations Contest by Serkan Yürekli. A new Tapa Variations Contest runs this weekend for those that are interested.

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to shift between shading mode and the composite Yajilin mode where left click marks cells, right click marks dots in cells or X’s on edges, left click+drag draws lines.)

Theme: Four Blocks

Rules: Standard Tapa rules.

Answer String: Enter the length in cells of each of the shaded segments from left to right for the marked rows, starting at the top. Separate each row’s entry from the next with a comma.

Time Standards (highlight to view): Grandmaster = 1:40, Master = 2:15, Expert = 4:30

Solution: PDF

PDF

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

Theme: Two Sides (the shading is just for artistic effect)

Rules: Standard LITS rules.

Answer String: Enter the length in cells of each of the shaded segments from left to right for the marked rows, starting at the top. Separate each row’s entry from the next with a comma.

Time Standards (highlight to view): Grandmaster = 1:20, Master = 1:45, Expert = 3:30

Solution: PDF

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to shift between shading mode and the composite Yajilin mode where left click marks cells, right click marks dots in cells or X’s on edges, left click+drag draws lines.)

Theme: 4×4 Clueless Square

Rules: Standard Tapa rules.

Answer String: Enter the length in cells of each of the shaded segments from left to right for the marked rows, starting at the top. Separate each row entry from the next with a comma.

Time Standards (highlight to view): Grandmaster = 2:30, Master = 3:45, Expert = 7:30

Solution: PDF

PDF

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

Theme: Threes Frame; an extra large Cross the Streams puzzle by its inventor, Grant Fikes, marking his 50th post here.

Rules: Standard Cross the Streams rules.

Answer String: Enter the length in cells of each of the black segments from top to bottom for the marked columns, going in order from A to B to C to D and separating each entry with a comma.

Time Standards (highlight to view): Grandmaster = 8:00, Master = 14:00, Expert = 28:00

Solution: PDF

(View image directly for larger form.)

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to shift between shading mode and the composite Yajilin mode where left click marks cells, right click marks dots in cells or X’s on edges, left click+drag draws lines.)

Theme: No border clues

Rules: Standard Tapa rules.

Answer String: Enter the length in cells of each of the shaded segments from left to right for the marked rows, starting at the top. Separate each row’s entry from the next with a comma.

Time Standards (highlight to view): Grandmaster = 3:00, Master = 5:00, Expert = 10:00

Solution: PDF

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to shift between shading mode and the composite Yajilin mode where left click marks cells, right click marks dots in cells or X’s on edges, left click+drag draws lines.)

Theme: Clue symmetry and logic

Rules: Standard Tapa rules.

Answer String: Enter the length in cells of each of the shaded segments from left to right for the marked rows, starting at the top. Separate each row’s entry from the next with a comma.

Time Standards (highlight to view): Grandmaster = 2:15, Master = 4:45, Expert = 9:30

Solution: PDF