Puzzle · Logic Puzzle
Gokigen Slant
Play Gokigen Slant online. Place a diagonal in every square. Meet the numbered vertex clues without creating a closed loop. Free in your browser.
The game's own interface may still be in English.
Overview
Gokigen Slant fills a square grid with diagonal strokes. Every cell receives either a rising slash or a falling slash. Numbers at grid vertices specify how many diagonals end at that point. The finished arrangement must contain no closed loop of diagonals, even if every numbered point has the correct count. Unnumbered vertices may have different numbers of incident strokes, so they remain important when checking cycles. This creates a compact visual puzzle with only two final states per square. The locally compiled Slant engine generates boards and offers size settings. A tiny orientation change can complete a remote-looking cycle through several unnumbered vertices, making the no-loop rule a useful source of deductions rather than just a final check.
How to Play
Click a square to draw a diagonal, then click again to cycle its orientation or clear it. Secondary clicking starts with the opposite orientation. Phone players can simply cycle with repeated taps or enable Secondary for more direct placement. Match the number of diagonal endpoints at every numbered vertex. Complete all cells while avoiding any closed chain of strokes. Undo corrects an orientation without restarting the board. Use Restart for a clean attempt on the same clues or New for another generated puzzle.
Tips & Strategy
A zero vertex excludes every diagonal that could reach it, while a four in the interior forces all four surrounding diagonals inward. Border clues have fewer possible incident strokes and often resolve sooner. After using these direct counts, trace partial chains whose endpoints are close together. If the final missing diagonal would join them into a loop, choose its opposite orientation even when no nearby number forces the decision. Revisit numbered vertices whenever one adjacent cell changes. Count endpoints carefully: a diagonal passing through a neighbouring square does not contribute unless its end actually lands on the numbered point.
About this version
Gokigen Slant uses the locally compiled slant engine from Simon Tatham’s Portable Puzzle Collection. The original authors retain credit under the MIT license. SonoTap provides the browser adaptation and this guide.
Controls
- Mouse
- Click a square to draw a diagonal, then click again to cycle its orientation or clear it. Secondary clicking starts with the opposite orientation. Phone players can simply cycle with repeated taps or enable Secondary for more direct placement. Match the number of diagonal endpoints at every numbered vertex. Complete all cells while avoiding any closed chain of strokes. Undo corrects an orientation without restarting the board. Use Restart for a clean attempt on the same clues or New for another generated puzzle.
- Touch
- Tap or drag on the board using the same rules as mouse input. Enable Secondary for the alternate mark; numeric games also provide on-screen keys.
Features
- Place a diagonal in every square. Meet the numbered vertex clues without creating a closed loop.
- Local open-source game engine with original author credits
- Generated puzzles and the upstream Type settings
- Undo and restart controls
- Touch input and a secondary-action toggle
Frequently asked questions
What is the goal in Gokigen Slant?
Place a diagonal in every square. Meet the numbered vertex clues without creating a closed loop.
What is a useful first deduction in Gokigen Slant?
A zero vertex excludes every diagonal that could reach it, while a four in the interior forces all four surrounding diagonals inward. Border clues have fewer possible incident strokes and often resolve sooner.