Puzzlerium tour: Pentominous (Cipher/Borders)

 Finally, it is time to end the year.

Rules: Divide the grid into some Pentomino shapes along the gridlines. The shapes may be used more than once, with rotations and reflections allowed. Identical shapes may not touch each other through the edges. Letters indicate that the corresponding cells are used by the shapes the letters usually represent. However, each letter is encrypted using a letter, each different given letter mapping to a different letter. The original letter for one of the given letters is already revealed below the grid.  Also, some borders are given.

Puzzlerium tour: Divisive Loop

 

Rules: Draw a loop that visits all of the outlined regions, entering and exiting each region  twice. The loop may not intersect itself or pass through a cell more than once. Within each region, the two blocks of consecutively visited cells do not share cell borders with each other. 

About :  Divisive Loop was invented by Anurag Sahay, and debuts with this puzzle.

Second Puzzlerium Optimization Championship : Results

Vladimir Burik won a second straight title. He found optimal solutions to 4 of the 6 puzzles and yet managed to win comfortably, a ghastly downside of inadequate participation. Detailed results were posted a few days ago on the LM forum. The best solutions and results table can be found here. 

Puzzlerium tour: Yajilin

Rules: Shade some cells and draw a single closed loop through all remaining white cells, the loop's path moving horizontally  or vertically through cell centers. Clue cells may not be shaded. The loop may not intersect itself,  or go through a cell more than once. Shaded cells cannot share an edge with each other. Some cells contain a number and arrow, or a question mark, and may not be part of the loop. Numbered arrows in such cells indicate

the total number of shaded cells in the direction of the arrow.

Puzzlerium tour: The Inner World

In recent years, we have been overwhelmed with puzzle inventions that have (sometimes incomprehensibly) complex rules. I am inclined to believe this puzzle doesn't exceed the complexity threshold. 

Rules: Draw a single loop by joining some of the vertices. The loop may not touch or cross itself. Each of the given numbers tells how many of the four surrounding edges are used. Also, divide the entire region inside the loop into sub-regions that are one cell or larger in size. Given numbers (in the interior of the loop) must equal the size (in number of cells) of the region they are in. No two regions of the same size may share an edge. It is possible that there exist regions without any given numbers.

About : The Inner world was invented by Anurag Sahay, and debuts with this puzzle.

Puzzlerium tour: Cave (LITSO)

Today's offering is an unmissable cave puzzle that has regions as givens.

 

Rules: Shade in exactly four cells in each bold outlined region, to leave behind a single connected group of shaded cells, with no enclosed, unshaded cells. In other words, all unshaded cells must be connected through other unshaded cells to an edge of the grid. Also, it must be possible to split the shaded region into tetrominoes L, I, T ,S and O, each shape contained in one outlined region, such that no two identical tetrominoes share an edge. 

Puzzlerium tour: Kakuro (Extra-digit)

Today's extraordinary puzzle is a Kakuro with extra digits.  

Rules: Fill in each white cell with one or two digits from 1 to 9. The sum of all of the numbers in every across or down row of uninterrupted white cells (including 'sum' of one number) must be equal to the clue given to the left or the top. If there are

two digits in a cell, they form a two-digit number. No digits may be repeated

within an uninterrupted row. No more than one cell in an uninterrupted row may contain two digits. Not all of the uninterrupted rows are required to contain an extra digit.

About : Kakuro (Extra-digit) was invented by Anurag Sahay and debuts with this puzzle.

Puzzlerium tour: Battleships (Invasion)

 

Rules: Locate the given fleet of 11 ships (including the 4x4 alien ship) into the given grid. Clues outside tell how many cells contain one of the regular ships in the corresponding row or column, but do not provide any information about the alien ship. Ships, the alien ship included, may be rotated, but may not touch each other, not even diagonally.

About : Invented by Anurag Sahay, this variant makes its debut with this post. 

Puzzlerium tour: Battleships (Cipher)

Rules: Each different letter stands for a different number and same letters stand for the same number. Find the correct match for each letter, then solve the battleships puzzle. 

Battleships rules: Locate the standard fleet of 10 ships into the given grid. Clues outside tell how many cells contain a ship the corresponding row or column. Ships may be rotated, but may not touch each other, not even diagonally.

About : It is believed that Battleships, in its earliest form, was invented by Jaime Poniachik in 1982.

Puzzlerium tour: Pentomino Areas

Pentomino Areas is an adaptation of the "Penta" puzzle, where outside clues are discarded and the grid is subdivided into regions to enforce new constraints on the pentomino shapes. Although I was not the first to write a Pentomino Areas puzzle, I certainly did bring it to the fore, inspiring several other Pentomino Areas works that followed. 

This enchanting genre opens up avenues for applying solving strategies generally not available to Penta. Quickly listing them down, one can most often do with three methods:

1. Identifying triples/quadruples that are the only possible shapes some of the regions can accommodate, leading to elimination through exhaustion (this is a dynamic list changing as you fill the regions) 

2. Marking cells that cannot be used by any shape.

3. Identifying the regions where a certain constrained shape can fit in.

Rules:  Place the full set of pentominoes into a 12x12 grid, one per bold outlined

region, with rotations and reflections allowed. Pentominoes cannot touch each other, not even diagonally. Also, each pentomino must be fully contained in its

containing region.