Step 6 of 6
Grass is free
Grass is free, it never lies, and it does most of the solving.
The rule of thumb: Marking impossible clearings costs nothing and narrows everything. Grass early, grass often — a board of grass is a board half solved.
Look back over the five techniques: every one of them spends half its life marking grass, and that’s the point. Each clearing you rule out narrows a line, feeds a count and starves a tree of options — the tents at the end are largely placed by the grass around them.
These practice boards are picked to prove it. Try to finish one tent-first — never grass a clearing, only pitch — and you stall: on each of them the grass rules alone decide a third or more of the clearings before a single tent is forced. When a real board feels stuck, the way forward is almost never a braver tent. It’s more grass.
Where to look: Your own habits. If you catch yourself scanning for tents, stop and scan for grass instead — the board you can’t finish is usually a board you haven’t grassed enough.
Worked example
A real position from a board that needs Grass is free. Purple: what the reasoning rests on. Dashed: the cells in question. Green: what it proves.
That’s the whole track: grass the zeroes, sweep the treeless, ring the tents, pair the trees, count the lines — and grass first, always. Every Easy board on the play page falls to these six. Play a full board →