JZC 2015

After JdZdC 2014, JZC 2015 was held in March. You can see puzzles here.
Maybe Round8 is useful for the 24HPC Japanese Round, isn't it?


This year, I prepared Round4 with Takeya. This round includes Classic Nurikabe and 3 variations.
Rules of variations are,
Overlapping:  each grid should be valid as Nurikabe
Pairs: from MellowMelon
Borderline: numbers on the edge must be placed in one of the two neighboring cells

And about bonus puzzles:
Top left: Classic Nurikabe
Top right: Pairs
Bottoms: as you can see from names and images


My main targets this year were,
To use hard classic logic and
To make intuitive Classic
In fact, both are I tried for a long time.

"Hard logic" is just reuse of what I know well, and some Japanese should be especially familiar with this logic. So the second target was rather harder, and I fully used my knowledge about how this type can be unique. I relied on solver for checking, and thanks to it, I think I obtained some new insights. They should be useless, though!


And I also made a Tapa for exhibition. As an exhibition puzzle, I tried to use some useful steps for competitions.