Yajisan-Kazusan Arrows: the watchman who counted steps
My cottage neighbor painted his fence and counted pickets out loud. I watched him and thought of arrows that count too.
The counting man
He painted every second picket and muttered: three this way, two that way. I asked why. He shrugged: to keep it even. A week later I opened Yajisan-Kazusan and met his doubles: arrows with numbers demanding an exact count of shaded cells in their direction. Click, the cell darkens. Click again, it clears. Arithmetic fenced across the field.
The arrow that fell silent
The field's main trick is this: an arrow in a shaded cell stops working. Its number demands nothing more. In my first game such a silent arrow stood in the center, seemingly demanding three cells to the right. I fought that row until I shaded the arrow itself for another, vertical one. And silence: the row is free, the condition lifted. I laughed out loud. The neighbor would understand: paint the picket, and you stop counting it.
The field as a fence
Since then I see the field as a fence. First I hunt arrows with small numbers: a one is almost always visible at once. Then I look for arrows I can switch off by shading them. I press Hint when the fence leans and my eye blurs: it shades one correct cell, and the grid straightens itself after that.
And the neighbor finished his fence, by the way. Even or not, I never recounted.