Cross-math puzzle guides
Learn the rules, use a repeatable solving method, and explore every Lattice world. Start with a free puzzle or go straight to the guide that matches your question.
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Learn the rules, find forced moves, and follow a complete solve from first clue to final tile.
- Basics · 7 minHow to Solve Cross-Math Puzzles (Step by Step)Learn how to solve cross-math puzzles without guessing: find the most constrained equation, place the forced number, and follow each crossing.
- Strategy · 5 minWhy every Lattice has exactly one solutionEvery Lattice puzzle is machine-proven to have a single, unique solution before it ships. Here's what that guarantee means and why it changes how the game feels.
- Strategy · 5 minDifficulty in Lattice, explained: Easy to MasterLattice grades puzzles by how deep the deduction goes, not how big the board is. Here's what Easy, Medium, Hard, Expert, and Master really mean.
- Strategy · 7 minA worked Master solve: cracking a cross-math puzzle step by stepWatch a Master-grade cross-math puzzle fall to pure deduction — no guessing — one forced step at a time, with the board shown at every stage.
Families, classrooms, and puzzle fans
Use cross-math for arithmetic reasoning and understand how it differs from other number-logic games.
- Basics · 6 minTeaching arithmetic reasoning with Lattice: a guide for parents and teachersHow Lattice's proven, no-guessing cross-math puzzles can help children practise mental arithmetic and learn to reason — with practical tips for getting started.
- Basics · 6 minLattice vs. Sudoku and KenKen: why proven cross-math goes furtherHow Lattice's cross-math compares to Sudoku and KenKen — and why proven-unique boards, a no-guessing guarantee, and twelve puzzle geometries make it the richer number-logic game.
- Reference · 4 minLattice glossary: cross-math terms explainedPlain one-line definitions of the cross-math and Lattice terms — cell, tile, tray, operator, chain, forced move, deduction depth, grade, worlds, and more.
Explore the Lattice worlds
See how diagonal paths, hidden operators, balances, rings, and 3D boards reshape the same core logic.
- Worlds · 6 minThe Weave: Diagonal Cross-Math and Bent Paths in LatticeA guide to The Weave world in Lattice, where cross-math equations run along diagonals and bent paths that cross like woven threads.
- Worlds · 6 minThe Forge and Mystery Ops: Minting Tiles and Deducing Hidden OperatorsHow to solve Lattice's Forge and Mystery Ops worlds: mint the number tiles you need and deduce the hidden operators between cells.
- Worlds · 7 minFrost, Balance, and Signs: Worlds Where Equations Judge ThemselvesA guide to three Lattice worlds where truth melts ice, two sides must match, and inequalities pin numbers down without naming them.
- Worlds · 6 minOrbits and Dials: Cross-Math in the RoundHow Orbits and Dials reshape cross-math into rings and spokes, and how to read a circular board one constrained equation at a time.
- Worlds · 6 minThe Cube and the Pyramid: Lattice's Two 3D WorldsHow Lattice's two three-dimensional worlds work, and how to solve cross-math that wraps a cube or climbs to a pyramid's summit.