The same logic, a new surface
The Cube and the Pyramid are the premium showpiece of Lattice, and they run on the same machinery as every flat board. Cells are joined by operators and equals, and you place number tiles so that every equation is true at once.
Nothing about the rules shifts when the board leaves the plane. Each puzzle is still machine-proven to have exactly one solution, so you never guess. What changes is the geometry. The board is now wrapped around a solid you rotate, and your job is to read that solid as a set of familiar 2D faces.
The Cube: equations that wrap a solid
In the Cube, the cross-math board wraps around all six faces of a cube you rotate in three dimensions. Each face on its own looks like an ordinary flat board.
The difference lives at the edges. Equations continue across face edges, so a chain can begin on one face and finish on the next. A cell that sits on an edge belongs to two faces at once. To work a chain that runs over a seam, you turn the cube so the start and the finish are both in view, then read the equation straight through the corner.
The Pyramid: every face feeds the summit
The Pyramid is built from triangular faces that rise toward a single apex, the summit cell at the very top. Equations climb each face upward.
Lower rows feed their values into the rows above them, and those rows feed the apex in turn. The summit is therefore determined by everything beneath it. You rotate the pyramid to work each face, and as the lower rows resolve, the value waiting at the summit narrows until only one tile can sit there.
Edges and shared cells are your leverage
In three dimensions, the seams are where the puzzle gives you the most. A cell shared by two faces is constrained from both sides at once, so it usually has the fewest values it can legally hold.
Start there. A shared cell is the best foothold because every fact you pin to it pays off twice, once on each face it touches. From a single solved edge cell, deductions tend to spread outward across both faces, the same way an anchored number opens up a flat board.
How to work in three dimensions
Treat each face as a 2D board you already know how to read. Solve what that face will give you, then mind the seams where it meets its neighbours.
Rotate deliberately rather than constantly. Keep the cell you are reasoning about and its immediate neighbours in view, so a chain that crosses an edge stays whole on screen. When a face stalls, turn to an adjacent face and look for a shared cell that the first face has already constrained. The new dimension is not a new kind of thinking; it is the same deduction, given room to wrap and climb.