Add blog post about two recently-published puzzles

My 12-Pentomino-themed Star Battle published today as well as my F is
for Fiendish Pentominous published a couple of weeks ago.

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+[[!meta title="Star Battle: Pentominoes, and Pentominous: F is for Fiendish"]]
+
+[[!tag puzzles]]
+
+I just had [my fifth
+puzzle](http://www.gmpuzzles.com/blog/2015/01/star-battle-carl-worth/)
+published at GM Puzzles.
+
+This was a fun one. It's my second Star Battle puzzle, and it's
+definitely more approachable than my previous dual-grid [Star
+Duel](star_duel/). (Incidentally, that giant Star Duel was noted as
+one among several of the [best object-placement puzzles of
+2014](http://www.gmpuzzles.com/blog/2014/12/best-2014-object-placement/)
+at GM Puzzles.
+
+I got the idea for today's Star Battle when reading that best-of
+post. One of the other puzzles noted there was this lovely
+[9-pentomino Star
+Battle](http://www.gmpuzzles.com/blog/2014/09/star-battle-zoltan-horvath/)
+by Zoltán Horváth. The post mentioned that another designer, Jiří
+Hrdina, had independently designed a similar 9-pentomino Star
+Battle. (I can't link directly to that one since it's not freely
+available on the web. It's contained in [The Art of Puzzles: Star
+Battle](http://www.gmpuzzles.com/store/the-art-of-puzzles) e-book
+available for sale). Then, in the comments, Matúš Demiger mentioned
+that he had also independently constructed a [third 9-pentomino Star
+Battle](https://www.dropbox.com/sh/ph4ntyc2r761r4c/AABpHTRWeX3eeqh82pRltc1va/03_24h_2014%20DEMIGER%20-%20PB.pdf?dl=0)
+as part of the [2014 24-Hour Puzzle
+Competition](https://www.dropbox.com/sh/ph4ntyc2r761r4c/iFyCTXGE7_).
+
+So at least three puzzle authors all happened to construct
+pentomino-themed Star Battle puzzles last year, and all three happened
+to choose the fairly-standard 10x10 grid size, (forcing the puzzle to
+include only 9 of the 12 possible pentomino shapes). Matúš's comment
+was "I hope someone will try to include all twelve pentominoes" and I
+couldn't resist the challenge.
+
+And it was an interesting challenge since putting 12 pentominoes into
+a Star Battle requires a 13x13 grid. That's not too much of a problem
+in and of itself, (my Star Duel used a 15x15 grid, for example). But
+with this particular theme, as the puzzle grows the total area of the
+pentominoes grows linearly, while the total puzzle area grows
+quadratically. In my final puzzle there are 12 regions of size 5 and
+then one giant outer region with 109 cells. But all 13 regions each
+only contain two stars. So the real challenge here was to ensure that
+when solving the puzzle the stars in the huge region didn't get
+determined early, (causing a bunch of cells to be wasted and forcing
+the user to tediously mark off all of the unused cells).
+
+Luckily, I think it just worked out. In all of my test-solving, the
+stars in the large region are among the very last determined.
+
+Anyway, give this puzzle a try if you'd like. The large number of tiny
+regions means there are a lot of easy steps early on in the
+puzzle. But there are still a few more interesting deductions in store
+later on, (but nothing ever all that difficult in this Wednesday-level
+puzzle).
+
+I should also thank Thomas Snyder for his editorial help. He found and
+fixed a small ambiguity in the first version of this puzzle that I
+submitted. I've since coded up a deductive Star Battle solver just to
+be able to verify uniqueness for puzzles I construct. But maybe I'll
+talk about that in a future post.
+
+PS. If anyone is following closely, I neglected to mention [my fourth
+puzzle](http://www.gmpuzzles.com/blog/2014/12/pentominous-carl-worth-2/)
+when it was published a few weeks ago on a Friday. It's a Pentominous
+puzzle with almost no clues other than 12 F's, and I named it "F is
+for Fiendish". The title is a warning, and I think it deserves it. I
+think this is the hardest puzzle I've published so far. My Star Duel
+earned a longer estimated "Expert" time, (37 minutes compared to 20
+minutes for "F is for Fiendish"), but that's mostly because Star Duel
+is so much bigger, (2 15x15 grids compared to a single 10x10
+grid). The deductions required here are definitely harder to find.
+
+My sister is really kind to do some of the initial testing of several
+of my puzzles. After I handed her a copy of "F is for Fiendish" one
+evening, she called me later that night to ask, "Can you email me a
+fresh copy of that puzzle? My husband and I have been trying it over
+and over and the paper is all disintegrating after so much erasing." That's a beautiful thing for a puzzle designer to hear---that someone is terribly frustrated with a puzzle, but still determined to stick with it and keep trying.
+
+So if you want a challenge, give ["F is for
+Fiendish"](http://www.gmpuzzles.com/blog/2014/12/pentominous-carl-worth-2/)
+a try. There are logical steps that can be found at every point to
+solve the puzzle without needing any guessing or back-tracking, (but
+they may not be easy to find). Good luck, and happy puzzling!