Star Battle Rules — How to Play
Everything you need to know about Star Battle, from the basic rules to advanced strategies. Includes a worked example and answers to common questions.
What is a Star Battle puzzle?
Star Battle is a pure logic puzzle. You get an N×N grid divided into N irregular regions by bold borders. Your task: place a fixed number of stars in the grid so that each row, each column, and each region contains exactly the right count. Stars cannot touch each other in any direction, including diagonally.
Unlike Sudoku or KenKen, there are no numbers to fill in. The only values are star or empty. The entire puzzle comes down to position: where can stars go, and where can they not?
The two rules
- Star counts. Place exactly S stars in every row, every column, and every bold-bordered region. S is the star count for the puzzle (1 for easier puzzles, 2 for harder ones). On a 1-star 6×6 grid, you place 6 stars total. On a 2-star 10×10 grid, you place 20.
- No touching. Stars cannot be adjacent to each other horizontally, vertically, or diagonally. Each star must have an empty cell in all 8 surrounding positions:
╳ ╳ ╳ ╳ ★ ╳ ╳ ╳ ╳
This is the defining constraint. It creates cascading eliminations that drive the whole solving process.
Worked example (6×6, 1 star)
Imagine a 6×6 grid with 6 regions. Each row, column, and region needs exactly 1 star. Here is how you might approach it:
- Scan for small regions. Find the region with the fewest cells. If a region has only 2 cells, the star must go in one of them. Check which cell, when starred, does not create an adjacency conflict with another required star.
- Place the first star. After placing a star, block all 8 adjacent cells. These cells cannot hold a star. Mark them with ×.
- Check affected rows and columns. The row and column containing the placed star are now satisfied (1 star each). Every remaining empty cell in that row and column can be marked ×.
- Propagate. The blocked cells may reduce other regions to a single valid position. If a region has only one unblocked cell remaining, place its star there.
- Repeat. Continue until all 6 stars are placed. Each placement triggers new eliminations, so the puzzle accelerates as you progress.
On a well-constructed 6×6 grid, 2 or 3 initial placements are usually enough to trigger a chain that solves the rest.
1-star vs 2-star puzzles
In a 1-star puzzle, each row, column, and region has exactly one star. Placing a star immediately satisfies its row, column, and region. All other cells in those units can be marked as blocked. This makes cascading eliminations fast and direct.
In a 2-star puzzle, placing one star in a region does not satisfy it — you still need a second star. The first star blocks neighbors, which may restrict where the second can go within the same region. The two stars must not touch, so long, narrow regions force them to the ends. L-shaped regions constrain placement to specific arms. Each region becomes a small sub-puzzle of its own, layered on top of the row and column constraints.
Most players find the 2-star variant significantly harder than increasing the grid size alone. The interaction between two stars within a single region creates reasoning chains that do not exist in 1-star puzzles.
Solving strategies
Small-region elimination
A region with S cells (where S is the star count) must have stars in every cell. A region with S+1 cells has one cell to leave empty. Enumerate the options and check adjacency constraints against neighboring regions.
Adjacency cascade
Every star blocks 8 cells. After placing a star, re-check all regions that overlap with the blocked zone. If any region is reduced to exactly S valid cells, place stars there.
Row/column counting
Count unblocked cells per row and column. If a row has S unblocked cells and needs S stars, fill them all. If a row has fewer unblocked cells than needed stars, you have an error — backtrack.
Region confinement
If a region's valid star cells all fall in one row (or column), that region “confines” the row. Other regions cannot place stars in that row within the confined columns. This technique bridges region constraints and line constraints.
Reverse confinement
If a row can only place its remaining stars from one region, that region's star(s) are confined to that row. Other cells in the region (outside the row) can be eliminated.
2-star pairing
In 2-star puzzles, enumerate valid pairs within each region. Filter by adjacency (the two stars cannot touch). Then cross-reference with row and column constraints to narrow down to one valid pair.
Star Battle vs Queens and LinkedIn Stars
LinkedIn's Stars game and the Queens puzzle are simplified variants of Star Battle. They use the same core mechanic — place one token per row, column, and colored region with a no-touch constraint — but with smaller grids and simpler region shapes.
| Aspect | LinkedIn Stars | Queens | Star Battle |
|---|---|---|---|
| Grid size | 5×5 – 8×8 | 5×5 – 9×9 | 6×6 – 14×14 |
| Star count | 1 | 1 | 1 or 2 |
| Region shapes | Simple/compact | Simple/compact | Irregular, complex |
If you enjoy LinkedIn Stars, Star Battle is the deeper version of the same idea. The 2-star variant and irregular region shapes create deduction chains that go far beyond what the casual versions offer.
Common mistakes
- Forgetting diagonals. The most common error. Stars block all 8 directions, not just 4. Check diagonals carefully.
- Not marking eliminated cells. On grids larger than 6×6, trying to hold eliminations in your head leads to mistakes. Mark blocked cells with × as you go.
- Guessing instead of deducing. Every Star Battle puzzle has a unique solution reachable through logic. If you need to guess, you are missing a constraint.
- Ignoring region shape. Long or L-shaped regions constrain star placement more than you might expect. Analyze region geometry before trying row/column approaches.
Frequently asked questions
What is a Star Battle puzzle?
A logic puzzle on an N×N grid divided into N regions. Place stars so each row, column, and region has exactly the required number. Stars cannot touch each other in any direction, including diagonally.
What is the difference between 1-star and 2-star Star Battle?
In 1-star, each row/column/region has 1 star. In 2-star, each has 2. The 2-star variant is much harder because two stars within a region must also avoid touching each other.
Is Star Battle the same as LinkedIn Stars?
LinkedIn Stars is a simplified version of Star Battle with smaller grids and simpler regions. Star Battle goes deeper with irregular shapes, larger grids, and 2-star configurations.
Can Star Battle puzzles be solved without guessing?
Yes. Every well-constructed puzzle has a unique solution reachable through logical deduction alone. Our puzzles are all verified to have exactly one solution.
What is the no-touch rule?
Stars cannot be adjacent horizontally, vertically, or diagonally. Each star needs an empty buffer in all 8 surrounding cells. This is also called the king-distance constraint.