Alternating Liars Masyu

Today’s puzzle is the second in an apparent series; that is, a series of not-quite-symmetrically clued Masyu variants. Here’s the first one, and it’s probably the harder of the two, at least if you’re trying to prove uniqueness. I quite like these both, which is why I’m publishing them in their faulty-symmetric glory. There’s also 6×6 starter, which showcases why I didn’t bother with colour antisymmetry.

Alternating Liars Masyu 1

Alternating Liars Masyu 2

Rules:

  • Draw a single non-self-intersecting loop that runs through the centers of the cells and visits all pearls.
  • On black pearls the loop must make a right turn, and the loop must go straight through the cells before and after the pearl.
  • On white pearls the loop goes straight through, and the loop must make a right turn on at least one of the cells before and after the pearl.
  • Additionally, every other pearl the loop passes through is a liar: that is, a white liar pearl acts as a black pearl, and vice versa.

Clouds

Here’s a Clouds puzzle.

Clouds 4

Rules:

  • Shade some cells to form rectangular clouds. The clouds don’t touch each other, even by corners.
  • A cloud must be at least two cells tall and wide: 1×n or n×1 clouds aren’t allowed.
  • The clues tell the amount of shaded cells in that row/column.

Tapa

Here’s an antisymmetric Tapa. I tried to keep the puzzle easy and the solving path flowing but not boring, please do tell if I succeeded.

Tapa 3b

(click for full size)

Rules:

  • Shade some cells to form a continuous wall that contains no 2×2 squares of shaded cells.
  • The clue numbers tell the size of continuous groups of shaded cells in the eight cells around the clues. Two groups must have at least one unshaded cell between them.
  • The clue cells themselves remain unshaded.

EDIT: The first version was ever so slightly ambiguous, so I had to remake the puzzle. The old version is here, if you’re curious.

Sum Skyscrapers Snake

I actually made yesterday’s snake puzzle a couple of months ago, and yesterday when posting it I realised that I have to make a sum variant. Maybe I’ll try a Haido snake next.

I really liked making this puzzle. Because I might have stuck to the theme too much, there’s a tricky step later on in the puzzle but otherwise it shouldn’t be too hard.

Sum Skyscrapers Snake 1

Rules:

  • Shade some cells to form a snake, an orthogonally connected non-branching path of cells.
  • The snake doesn’t touch itself orthogonally. That is, if you numbered the cells of the snake from head to tail, the only shaded cells directly adjacent to a shaded cell would be the next and previous cells in sequence. However, touching by corners is okay.
  • The numbers outside the grid act as Sum Skyscrapers clues:
    • On a row/column, a segment of n shaded cells is taken to be a skyscraper of height n.
    • A skyscraper blocks visibility of any other skyscraper behind it that’s not taller.
    • Looking from the clue’s direction, a clue tells the sum of the visible skyscrapers’s heights.

Skyscrapers Snake

The hardest part about this puzzle is probably the break-in.

Skyscrapers Snake 1a

Rules:

  • Shade some cells to form a snake, an orthogonally connected non-branching path of cells.
  • The snake doesn’t touch itself orthogonally. That is, if you numbered the cells of the snake from head to tail, the only shaded cells directly adjacent to a shaded cell would be the next and previous cells in sequence. However, touching by corners is okay.
  •  The numbers outside the grid act as Skyscrapers clues:
    • On a row/column, a segment of n shaded cells is taken to be a skyscraper of height n.
    • A skyscraper blocks visibility of any other skyscraper behind it that’s not taller.
    • Looking from the clue’s direction, a clue tells the amount of visible skyscrapers on its row/column.

Notice that unlike in Finnish Snake, the head, tail and length of the snake aren’t given, and the snake can touch itself diagonally.

Heyawake

Here’s a Heyawake. I used to hate Heyawake, but after making the first one (doubled with TLSI) I quite like them now.

Heyawake 2

(click for full-sized image)

Rules:

  • A region’s clue tells exactly how many shaded cells it contains. Unclued regions may have any number of shaded cells (including zero).
  • Two shaded cells may not share an edge.
  • The unshaded cells must form a single, continuous polyomino.
  • No continuous line of unshaded cells may pass over two or more region borders.

Finnish Snakes

Here’s a pair of Finnish Snakes. One puzzle’s shaded givens (dark gray cells) are the others’ blank givens (light gray cells), and vice versa (ignoring the head and tail). Sticking to the symmetric layout and duality restrictions probably made both puzzles a little worse than what they could’ve been alone, though. I also couldn’t get the lengths match up.

I was going to use white/black circles instead of coloured cells, but couldn’t bother in the end.

Finnish Snake 1

Finnish Snake 2a

Rules:

  • Shade some cells to form a snake.
  • The snake must use all dark gray cells, and none of the light gray cells.
  • The head and tail (numbered cells) are given, and indicate the snake’s length (49 and 47 cells long, respectively).
  • The snake doesn’t touch itself, even by corners.

EDIT: On the second snake, fixed the clue at R1C5.

Trinudo

Today’s puzzle is a Fillomino variant. Yet again I don’t know the creator of this puzzle type, or if the name matches the original. If you know, please tell me in the comments, etc. (Edit: Thanks!)

I quite like this variation, there’s something satisfying in how it tends to flow nicely.

Tatamino 1

Rules:

  • Divide the grid into polyominoes of size 1, 2 or 3.
  • Polyominoes of the same size may not share an edge.
  • A clue tells the size of the polyomino the cell belongs in.

For a harder version, remove the clues from R2C5 and R4C7.

TSLI / Heyawake

I’m not sure if today’s puzzle enritely qualifies as a double, since one puzzle uses numbers while the other doesn’t.

TSLI is a LITS variant. TSLI is to LITS as Pata is to Tapa, hence the naming.

I actually made the TSLI first, and as an afterthought decided to make a Heyawake with the same grid. It’s the first Heyawake I’ve made, and considering how much trouble I have solving Heyawakes, it turned out surprisingly good.

 

TSLI 1

TSLI rules:

  • Shade some cells to form a continuous wall that contains no 2×2 squares of shaded cells.
  • Each region contains exactly four unshaded cells, and they must form an L, I, T or S tetromino. Tetrominoes of the same shape may not share an edge.

 

Heyawake 1

Heyawake rules:

  • A region’s clue tells exactly how many shaded cells it contains. Unclued regions may have any number of shaded cells (including zero).
  • Two shaded cells may not share an edge.
  • The unshaded cells must form a single, continuous polyomino.
  • No continuous line of unshaded cells may pass over two or more region borders.
  • To clarify the last rule, the scenario below is illegal, but the one below it legal.

heyawakeexample

heyawakeexample2

EDIT: Turns out both puzzles were broken, both had slight ambiguities. That’s what happens when I make puzzles while delirious with fever, and have no test-solvers to boot…

The fix isn’t elegant, but I like the rest of the TSLI too much to completely retool the lower left corner. The Heyawake was reclued too.

(The dot means that the cell is unshaded.)

Outside Nurikabe

This is the sibling to today’s Outside Nurikabe on the GMPuzzles blog. It’s harder, but shouldn’t be as bifurcation-heavy as the first one was.

Outside Clue Nurikabe 2

Rules:

  • Unlike in regular Nurikabe, the clue numbers have been placed outside the grid.
  • The clues will appear in the first unshaded cell in the clue’s row/column, counted from the clue’s direction.
  • Standard Nurikabe rules then apply:
    • Shade some cells to form a continuous wall that contains no 2×2 squares of shaded cells.
    • The clue numbers hint at connected groups of unshaded cells.
    • Every group has exactly one clue, which tells the group’s size.