# Puzzle 83: Pentominous Borders

Another Pentominous Borders, presumably closer to what we’ll get on the GP.

Rules Split the grid into pentominos by placing some walls between cells. Pentominos that touch by an edge must be different, where two pentominos are considered the same if one can be rotated and/or reflected to become the other. Some walls are already given. Black cells aren’t part of the grid.

Or see the instruction booklet.

# Puzzle 82: Pentominous Borders

Here’s a Pentominous Borders, a type that will be on the US GP round next weekend.

Rules Split the grid into pentominos by placing some walls between cells. Pentominos that touch by an edge must be different, where two pentominos are considered the same if one can be rotated and/or reflected to become the other. Some walls are already given. Black cells aren’t part of the grid.

Or see the instruction booklet.

# Puzzle 75: Tapa LITS

The next Tapa Variations Contest is coming up: TVC XVIII. Once again, Bram is kindly sharing a set of practice puzzles (intro, part 1). To give a little bit back, here’s one more Tapa LITS.

One other of the types that will show up is Different Tapa, so solve the one from this blog if you haven’t: Puzzle 70: Different Tapa.

Rules Solve as a standard Tapa. In addition, the shaded cells must form a valid LITS solution (minus the rooms), i.e., the wall consists of tetrominos, and similar tetrominos can’t touch by edge.

# Puzzle 63: Starwars

This is a Starwars puzzle, another of the types on the GP. Inspired by a certain puzzle on the portal.Rules Place stars in some cells, such that cells with stars don’t touch, not even diagonally, and such that each row, column, area and line has exactly two stars.

# Puzzle 61 & 62: Neighbors

Here are two neighbors puzzles, a type which features on next weekend’s Dutch round of the WPF Puzzle GP. This time there is plenty of practice material, see Richard’s comment on the GP forum.

I made the second one first, but it appears I broke or imagined some of the logic. It does seem to have turned out unique. Usually I wouldn’t post it, but maybe it’s good practice for dealing with an impenetrable puzzle? If you find a nice way through, do let me know.

Rules Place a digit between 1 and 3 in every cell, such that each row and column contains exactly three copies of each. A cell is shaded if and only if the digit that it contains is different from all orthogonally adjacent digits.

# Puzzle 54: Lakes

The next GP round is coming up the weekend after next; this time it’s Slovakia’s turn. I’m very much looking forward fo this, after a great first round by Serbia. In that contest, I was particularly impressed by the Fillominos, which didn’t seem like they should turn out unique. It’s a bit early to judge this now, but I quite like the approach of multiple puzzles each of a limited set of types that seems to be followed throughout the GP.

For the Slovakian round, one of the less common puzzle types is Lakes (Regionen). I haven’t been able to find many examples, aside from those in the black-and-white matrix of the 2013 WPC Practice Mini-Marathon and the 2013 Beijing WPC. Do you know any more? Here’s one.

Rules Shade some cells, leaving some orthogonally connected regions of unshaded cells, containing one clue each. Clues indicate the size of the unshaded region that they’re a part of.

Or see the instruction booklet.

Here’s a practice puzzle for the other non-standard type on the Serbian GP this weekend, “Slitherlink Out-Liars” as they call it. I’m not too sure this one is representative of the type; certainly it feels different than the others I’ve solved.

Rules Draw a single loop that doesn’t touch or cross itself by connecting dots horizontally and vertically. Clues inside the loop indicate the number of adjacent edges used by the loop. Clues outside the loop indicate the number of adjacent edges used by the loop, plus or minus 1. Or see the instruction booklet.

Some more puzzles: 2010 German qualification. On croco puzzle: 2013-12-21, 2014-02-08, 2014-04-26. There was also one in the 2014 WPC.

# Puzzle 52: Shikaku knapp daneben

One of the non-standard puzzle types in the Serbian Grand Prix round is Shikaku with clues that are off by one (as “Shikaku Liars”). Here’s a practice puzzle.

Rules Split the grid into rectangles composed of grid cells, containing one clue each, such that the size of each rectangle is equal to the corresponding clue ±1. Or see the instruction booklet.

There’s another easier puzzle of this type on the Rätselportal: Knapp daneben – Rechtecke. Then, in the knapp daneben instance of the Hausigel Contest Series. The double-clue Shikakus on croco should also be good practice: 2014-03-012014-04-04.