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.
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.
Today marks the start of a series of Checkered Fillominos on croco-puzzle, check them out! (Solving on time will require making an account; they become freely playable after one week. No Java required.)
Here’s an extra one; the croco series starts out a bit more gently than this.
To welcome the new year, here’s a Tapa “knapp-daneben”, i.e., all clues are off by one. The type features on Tapa Variations Contest XVII which takes place on the week-end. I’m really looking forward to that! For a more thorough preparation, check the practice puzzles on Bram’s blog. 
Rules Increase or decrease each digit by one, then solve as a regular Tapa. Digits may become zero, even multiple, but not negative.
Here’s another WPC practice puzzle, a Magic Summer from the round of puzzles with different areas, just like the recent Different Tapa.
While on the topic of WPC puzzles: There’s a WPC series starting today on croco-puzzle. It’s authored by Silke and me, with a selection of puzzle types from Sofia. These are all “Ü2”, so you can solve them with no Java applet worries.
Rules Place digits in some cells, so that each row and column contains exactly digits 1 through 5.
Connected blocks of digits in a row or column form numbers by reading left to right or downwards, respectively. Clues outside the grid are equal to the sum of all such numbers within the corresponding row or column.
In addition, the gray cells must all have different content.
Here’s a practice puzzle that I made for the color-themed team round at the WPC. Some of the intended logic may have been lost in getting it correct, but enjoy nonetheless.
Rules Place some red, green and blue light bulbs. These shine in vertical and horizontal direction until they hit a black cell. Every white cell must be illuminated, and no two bulbs may illuminate each other. Colored clues indicate the composite color of the bulbs that illuminate it: pure red, green or blue, cyan (green+blue), magenta (red+blue) or yellow (red+green).
Or see the WPC instructions.
I’m meaning to write up a report on the recently finished 24th WPC. No official results yet, but Ken Endo won the individual competition before Ulrich Voigt and Palmer Mebane, and we (Florian, Philipp, Ulrich and I) took gold with the team in front of Japan, Germany B (inofficial) and USA.
Instead, here’s a puzzle I made in preparation for round 9, which consisted of various puzzles built around the idea of marking several areas that had to be filled differently.
Rules Solve as a standard Tapa. Additionally, each gray 2-by-2 square must be shaded differently. E.g., no two gray squares can have only the top left corner shaded.
There are 15 gray squares, the different shades of gray are only there to make it possible to tell the squares apart.
Edit Here’s an alternate rendering, due to edderiofer.
This is a Pentominous puzzle.
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.
Angle Loop is a puzzle type that I first saw in Toketa Vol. 2. There’s a lot of great puzzles in there, but this type really stands out. Two puzzles below.
Maybe Puzzles 