I hope you enjoy these Checkered Fillominos as much as I do. This one came out clearly too hard for this year’s 24h puzzle championship in Budapest. (April 17-19, I don’t think it’s too late to join.)
EDIT Fixed an amibiguity. (Hopefully. Thanks Prasanna for finding it.)
The German qualification is through. The puzzles will be available there again sooner or later, maybe I’ll post my contribution to the set here later. Here’s a somewhat trickier Checkered Fillomino that didn’t make it. I’m not sure it’s right to tag it as hard, that depends a lot on how well you know the type. 
The online qualification tournament for this year’s German Logic Masters is taking place next weekend, authored by Silke Berendes and me. It’s open as a contest to everybody. Let us know on the forum if anything’s unclear in the instruction booklet (the English version hasn’t been proof-read extensively).
Here’s a Double Back puzzle that didn’t make the cut.
One more Lakes puzzle. Enjoy!
EDIT Some more of this type, thanks to EKBM and Zoltán: http://inabapuzzle.com/honkaku/paintp.pdf (by Inaba Naoki), http://5mp.eu/fajlok/logikairejtveny/tavak.372.380_www.5mp.eu_.pdf
Some more Slovak Sums, see the previous one for the rules. This one is certainly more difficult.
Here’s another GP preview puzzle. It’s a bit degenerate, but maybe it’s still useful? For this type, there’s a bit more material out there:
Rules Place digits from 1 to 4 in some blank cells, so that each row and column contains each digit exactly once. Clue numbers indicate the sum of orthogonally adjacent digits. The number of circles under a clue number indicates the number of digits involved in this sum. Or see the instruction booklet.
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.
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: 2014-03-01, 2014-04-04.
Long time no post. Same excuse as last time around. With this year’s puzzle GP starting this weekend with the Serbian round, some preview puzzles are in the queue. For now, I’ll link to a couple of my puzzles that were published elsewhere:
Maybe Puzzles 