The techniques
How to solve Star Battle
Every Star Battle worth its name solves by pure deduction — never a guess. This is the full ladder of techniques, ordered the way difficulty actually climbs: from the housekeeping you do without thinking, up to the deep look-aheads that separate a Very Hard from the rest.
The one habit behind every technique
Beginners hunt for where stars go. Strong solvers spend most of their time proving where stars can't go — dotting squares out until a star is the only thing left that fits. Every technique below is a different way of ruling squares out with certainty. String enough of them together and the board solves itself.
The golden rule
If you're ever tempted to guess, there's a forced move you haven't found yet. In a properly made puzzle the next deduction always exists — the skill is spotting it.
The technique ladder
Six tiers, easiest first. Zavija names the tier of every hint and every move in your post-solve review, so you always know how hard the move you just made really was.
Bookkeeping, not deduction — but skip it and you'll miss everything else. A star rules out its whole row, column, region, and the eight touching squares; marking those is housekeeping.
- Housekeeping — a square already killed by a star's row, column, region, or one of its eight neighbours. Dot it and move on.
The easiest real moves: a unit has only one place left for a star it still owes, so the star goes there.
- Last cell — a region, row, or column has exactly one open square left for its remaining star.
- Last cells — a unit has only as many open squares as stars it still needs, so all of them are forced.
A region's star is pinned to a single row, column, or tight cluster — so everything it can't reach clears.
- Region locked to a row / column — a region's star can only sit in one line, so the rest of that line clears.
- Row / column locked to a region — a line's open squares all lie in one region, so that region's cells elsewhere clear.
- Shape elimination — every way a region can place its star touches this square, so it's ruled out.
- Confinement & chunk confinement — a region's stars are trapped in one line or sub-cluster, forcing some cells and clearing others.
- Crowding — a star here would pack a row or column too tightly to fit its own non-adjacent stars.
Counting stars across several rows, columns, and regions at once to lock down where they must go. This is where Star Battle gets its teeth.
- Counting — weigh the stars a band of rows or columns owes against the regions inside it; the arithmetic pins the rest down.
- N-set / fish — a set of regions can only place their stars across an equal number of lines, clearing those lines' other cells.
- N rows / N regions (and its mirrors) — N rows whose stars must all live in the same N regions, so those regions clear elsewhere.
- Squeeze — a region can't fit its stars off a line, so it's squeezed onto it.
- Carried confinement — facts banked from earlier moves keep pinning a region's stars into set groups.
One-ply exclusions: place a star in your head and a region or a star-count breaks immediately — no long chain needed.
- Forward elimination — put a star here and some region instantly can't reach its quota, so the square is out.
- Relay — a star here forces a second star elsewhere, and the pair together leave a unit with no room.
- Either-or — a unit's star sits in one of two spots, and both spots force the same elimination.
- Forced-line count / line saturation — a star here would push two regions to over-fill one line, or a line's star can come from only one region.
- Composite count — pin a region's star to a small area, then count the crossing lines using that fact.
The hardest, most deliberate moves: place a star in your head and follow the single forced line of play until it contradicts — proving the star was impossible.
- Look-ahead — assume a star, follow the one forced continuation, and hit a contradiction several moves out. A clean look-ahead is a deduction, not a guess — the difference is that every step in between was forced.
Guessing vs. deduction — the line that matters
The dividing line in Star Battle isn't hard vs. easy. It's whether every step was forced. A look-ahead where each move follows necessarily is real solving. Picking one of two candidates "to see what happens" is a guess — even if it turns out right.
That distinction is exactly what Zavija's post-solve review measures. It replays your own solve move by move and shows where you reasoned it out, where a simpler line was sitting right there, and where you guessed instead of deduced — like a chess.com Game Review, for a logic puzzle. It's the fastest way to actually get better.
Where a puzzle's difficulty really comes from
Two puzzles can both need "counting" and feel worlds apart. Zavija's engine breaks difficulty into three parts:
- Hunt — how hard the next move is to find. A move can be simple to execute but buried among dozens of candidates.
- Snags — how much careful housekeeping the board demands, where one missed dot quietly derails you.
- Gate — the single hardest technique the puzzle forces you to use. A puzzle is only as easy as its toughest required step.
Common questions
What technique should I learn first?
Master singles and confinement (T1–T2). They solve most easy and medium puzzles outright and set up every harder move. Counting (T3) is the first real "aha" tier.
How do I solve a hard puzzle without guessing?
Reach for counting and forcing. Count the stars a band owes against its regions, or place a star mentally and show it breaks a unit on the very next step. There is always a forced move — a guess just means you haven't found it yet.
Is look-ahead the same as guessing?
No. In a look-ahead every intermediate step is forced, so the contradiction is a proof. Guessing branches into a line that isn't forced. Same-looking, opposite in rigour.
Where can I see these on a real board?
Inside Zavija, every hint names its technique and the review tags each of your moves — with a worked example you can step through. Try this week's free puzzle.
Practice the whole ladder.
Zavija names the technique when you're stuck and reviews every move after — the fastest way to level up.