# List of Tapa variants

There are hundreds of Tapa variants. Serkan Yürekli has compiled a list of Tapa variations, including all of those that have appeared on his Tapa Variation Contests. The followings are mostly extraction from the list. The base rule of Tapa is based on rules from WPC 2019 IB.

### Pata[edit]

Invented by Mehmet Murat Sevim (Turkey) in 2010. First appeared on TVC I. The puzzle was written by Serkan Yürekli.

Shade some cells so that all shaded cells are connected and no 2x2 square is completely shaded. Cells with numbers cannot be shaded. The unshaded numbers indicate how many of the neighbouring cells are shaded. Each number corresponds to a contiguous group of **unshaded** cells, two such groups are separated by one or more unshaded cells.

(Example from WPC 2015 IB)

### Tapa Islands[edit]

The rules were proposed by Jan Mrozowski (Poland). Hybrid with Nurikabe, sometimes called Islands. First appeared on TVC IV (2010). The puzzle was written by Serkan Yürekli.

Shade some cells so that all shaded cells are connected and no 2x2 square is completely shaded. Cells with numbers cannot be shaded. The unshaded numbers indicate how many of the neighbouring cells are shaded, and these shaded cells form a contiguous group.

Moreover, each white region contains at most one clue cell. If there is a clue cell in a white region, one of the digits gives the size of that area.

#### Rule variations[edit]

- A puzzle from WPC 2018/Round 6, "Nurikabe Tapa", only featured single-numbered clues and required every white region to contain a clue cell, thus being closer to Nurikabe. The author of the puzzle was Jan Zvěřina (Czech Rep.)

### Easy as Tapa[edit]

The rules were proposed by Andrey Bogdanov (Russia). Hybrid with Easy as-style clues. First appeared on TVC IV (2010). The puzzle was written by Serkan Yürekli.

Place clues in the grid so that there exists a solution under given rules and then solve the remaining puzzle.

Rules (normal Tapa rules): Shade some cells so that all shaded cells are connected and no 2x2 square is completely shaded. Cells with numbers cannot be shaded. The unshaded numbers indicate how many of the neighbouring cells are shaded, and these shaded cells form a contiguous group.

The numbers outside the grid indicate the clue cell first seen from the corresponding directions.

### Twilight Tapa[edit]

Invented by Nils Miehe (Germany) in 2010. First appeared on LMD portal.^{[1]}

Shade some cells so that all shaded cells are connected and no 2x2 square is completely shaded. Cells with numbers cannot be shaded. The unshaded numbers indicate how many of the neighbouring cells are shaded. Each number corresponds to a contiguous group of shaded cells, two such groups are separated by one or more unshaded cells. **Similarly, the shaded numbers indicate how many of the neighbouring cells are unshaded.**

### Tapa Line[edit]

Invented by Palmer Mebane (USA) in 2011. First appeared on Palmer's blog.^{[2]}

Shade some cells so that all shaded cells are connected and no 2x2 square is completely shaded. Cells with numbers cannot be shaded. The unshaded numbers indicate how many of the neighbouring cells are shaded. Each number corresponds to a contiguous group of shaded cells, two such groups are separated by one or more unshaded cells.

Additionally, there may not be four consecutive shaded cells in any row or column.

(Example from WPC 2017 IB)

### Tapa Double Back[edit]

Invented by Bram de Laat (Netherlands) in 2011. First appeared on Bram's blog.^{[3]}

Shade some cells so that all shaded cells are connected and no 2x2 square is completely shaded. Cells with numbers cannot be shaded. The unshaded numbers indicate how many of the neighbouring cells are shaded. Each number corresponds to a contiguous group of shaded cells, two such groups are separated by one or more unshaded cells.

Additionally, each region must be occupied by two separate segments of shaded cells.

(Example from WPC 2017 IB)

### Tapa Trimino[edit]

Invented by Rohan Rao (India) in 2011. First appeared on TVC VI.

Shade some cells so that all shaded cells are connected and no 2x2 square is completely shaded. Cells with numbers cannot be shaded. The unshaded numbers indicate how many of the neighbouring cells are shaded. Each number corresponds to a contiguous group of shaded cells, two such groups are separated by one or more unshaded cells.

Additionally, shaded cells must be able to be tiled with L-trimino.

(Example from WPC 2017 IB)

#### Rule varaiations[edit]

- Theoretically this can work with any polyomino other than L trimino. One that uses T pentomino appeared in WPC 2014/Round 13 under the name
**T for Tapa**. One that uses an unidentified pentomino that solvers must determine appeared in WPC 2016/Round 17. For clarity, here the puzzle that uses other polyominoes than triminoes is referred to as**Tapa Pentomino**and such.

### Thermometer Tapa[edit]

Invented by Rohan Rao (India) in 2011. First appeared on TVC VI. The name is influenced by Thermometers.

The grid contains thermometers that can be completely used, partially used or completely unused. The mercury rises starting from the head (rounded end) to the tail, without skipping any segments.

### Alternative Tapa[edit]

Invented by Serkan Yürekli (Turkey) in 2011. First appeared on TVC VI.

Shade some cells so that all shaded cells are connected and no 2x2 square is completely shaded. Cells with numbers cannot be shaded. The numbers indicate how many of the neighbouring cells are shaded. Each number corresponds to a contiguous group of shaded cells, two such groups are separated by one or more unshaded cells.

Additionally, for each set of identical letters, only one must be shaded.

(Example from WPC 2017 IB)

### Hungarian Tapa[edit]

Invented by Zoltan Horvath (Hungary) in 2011. First appeared on TVC VII.

Place numbers in the given range into some cells so that all numbered cells are connected and no 2x2 square is filled with numbers. The wall should only be made up of the digits from the given range. Each row and column should contain the digits from the given range exactly once. Tapa clues indicate the sums of the separate blackened cell blocks in the neighbouring cells.

(Example (1-4) from WPC 2019 IB)

### Kakuro-Style Tapa[edit]

Invented by Anurag Sahay (India) in 2012. First appeared on Anurag's blog.^{[4]}

Additionally, clues in black cells represent the number of separate blackened blocks in the corresponding directions. For any direction provided with a clue, the separate blocks should be of different lengths.

(Example from WPC 2017 IB)

### Tapa Skyscrapers[edit]

Invented by Prasanna Seshadri (India) in 2012. First appeared on Prasanna's blog.^{[5]}

Additionally, numbers outside the grid show the number of separate wall segments visible in that direction. A segment of length n is taken as a skyscraper of height n. Skyscrapers of length n can block visibility of other skyscrapers of length n and below.

(Example from WPC 2017 IB)

### Twopa[edit]

Invented by Prasanna Seshadri (India) in 2013. First appeared on TVC XV.

Furthermore, in the given two grids, every clue must behave differently.

### Color Tapa[edit]

First appeared on Tawan Sunathvanichkul's (Thailand) blog post^{[6]} in 2014.

The shaded cells will be coloured with three colour segments (blue, yellow, and red). Each coloured segment must be contiguous. The coloured numbers describe the mix of colours surrounding that cell. The **subtractive** mixture of three primary colours will result in a secondary color. (green = blue + yellow, orange = red + yellow, purple = red + blue)

(Rules and example from WPC 2015 IB)

### Tapa Groups or Cells[edit]

Hybrid of Tapa and TapaQ. Invented by Christian Halberstadt (Germany) in 2014. First appeared on LMD portal.^{[7]} TapaQ was invented by Sebastian Matschke (Germany) in 2009.

Shade some cells so that all shaded cells are connected and no 2x2 square is completely shaded. Cells with numbers cannot be shaded. Each number has one of two meanings:

- The number indicates how many of the adjacent cells are shaded, and these shaded cells form a contiguous group, or
- The number indicates how many separate groups of shaded cells are adjacent.

Clues may conform to both meanings.

(Rules (modified) from WPC 2019 IB, example by EctoPlasma)

### Full Tapa[edit]

First appeared on WPC 2016/Round 4, "Full Classics" round. The idea was by Matej Uher (Slovakia).

Shade some cells to get a valid Tapa solution:

Shade some cells to create a continuous region of shaded cells. Numbers in the remaining (unshaded) cells indicate the lengths of consecutive shaded blocks in the cells neighbouring orthogonally and diagonally. If there is more than one number in a cell, there must be at least one white cell between the shaded blocks. Shaded cells cannot form a 2×2 square.

(Rules and example from WPC 2016 IB)

### Disguised Knights Tapa[edit]

First appeared on WPC 2017/Round 6. The puzzle was by Prasanna Seshadri (India).

Additionally, the Tapa clues also describe the 8 cells that are a knight step away from them, in the same spacing considerations as the usual 8 cells, including the fact that the cells going out of the grid do not factor in the spacing.

(Rules and example from WPC 2017 IB)

### LITS Tapa[edit]

Not to be confused with Tapa LITS. The additional rule is loosely based on LITS rules. First appeared on WPC 2018/Round 6. The puzzle was by Jiří Hrdina (Czech Rep).

Place some tetrominoes in the empty cells so that they form a continuous wall with no 2×2 regions. Tetrominoes of the same type cannot touch each other by sides. The hints indicate all the tetromino segments in the surrounding 8 cells in no particular order. Each segment is created by all the adjacent cells of the same tetromino type (rotation or reflection of the tetromino does not change its type).

(Rules (modified) and example from WPC 2018 IB)

## Appearances in the past WPCs[edit]

- WPC 2019/World Cup Round 1 (Hungarian Tapa) by Roland Voigt
- WPC 2019/Round 8 (Twilight Tapa) by Rainer Biegler
- WPC 2019/Round 11 (Tapa Groups or Cells - Hexagonal) by Christian Halberstadt
- WPC 2018/Round 6 (Tapa Islands) by Jan Zvěřina
- WPC 2018/Round 6 (LITS Tapa) by Jiři Hrdina
- WPC 2017/Round 6 (Alternative Tapa, Twopa, Tapa Skyscrapers, Thermometer Tapa, Kakuro-style Tapa, Disguised Knights Tapa, Tapa Line, Tapa Double Back) by Prasanna Seshadri
- WPC 2017/Round 6 (Tapa Trimino, Instructionless Tapa) by Rohan Rao
- WPC 2016/Round 4 (Full Tapa) by Matúš Demiger and Matej Uher
- WPC 2016/Round 12 (Alternative Tapa) by Matúš Demiger
- WPC 2016/Round 17 (Tapa Pentomino) by Matej Uher
- WPC 2015/Round 5 (Easy as Tapa) by Andrey Bogdanov
- WPC 2015/Round 7 (Colour Tapa) by Tawan Sunathvanichkul
- WPC 2015/Round 10 (Pata) by Svetlozar Stefanov

## References[edit]

- ↑ https://logic-masters.de/Raetselportal/Raetsel/zeigen.php?chlang=en&id=0000F0
- ↑ https://mellowmelon.wordpress.com/2011/07/29/puzzle-343/
- ↑ http://puzzleparasite.blogspot.com/2011/12/puzzle-70-tapa-double-back.html
- ↑ http://anuragthefirst.blogspot.com/2012/09/kakuro-style-tapa_3.html
- ↑ https://prasannaseshadri.wordpress.com/2012/06/17/puzzle-no-172-tapa-skyscrapers/
- ↑ https://roygbivpuzzles.wordpress.com/2014/01/19/solutions-to-colour-restore-34/
- ↑ https://logic-masters.de/Raetselportal/Raetsel/zeigen.php?id=0000QQ