1. Pick a piece
Tap one of the twelve four-hex pieces (A to L). Press ⟳ or the R key to turn it by 60°. Mirror shapes are separate pieces.
Make Your board match the Target exactly, in shape and in colour. You stamp four-hex pieces, and each stamp flips one colour on the hexes it covers.
Tap one of the twelve four-hex pieces (A to L). Press ⟳ or the R key to turn it by 60°. Mirror shapes are separate pieces.
Pick Cyan, Magenta or Yellow (keys 1, 2, 3). Each stamp flips only that one colour on the hexes it covers.
Point at a hex: the piece sits around it (blue outline). Near the edge it slides in to fit. Click, or tap on a phone. A red outline means it cannot fit there.
If a hex already has Cyan and you stamp Cyan on it again, the Cyan turns off. The same is true for Magenta and Yellow.
Different colours stay on together: Cyan + Magenta is purple, Cyan + Yellow green, Magenta + Yellow orange. All three together look dark plum.
When every hex matches, Mismatch shows 0. Stuck? Hints (H) outlines the wrong hexes in red, and Solution shows the stamps one by one.
Goal: make Your board match the Target exactly (shape and color). You place four-cell tetrahex stamps on an axial hex grid.
Stamping uses XOR (toggle): stamping the same CMY color on a cell twice cancels it back.
Color = 3-bit CMY state per cell. Each cell stores three on/off bits: Cyan (C), Magenta (M), Yellow (Y).
A stamp flips exactly one bit (C or M or Y) over its footprint.
- One bit on: pure C/M/Y
- Two bits on: mix (C+M, C+Y, M+Y)
- Three bits on (C+M+Y): shown as dark/black
- Zero bits: empty/paper
Overlaps matter because XOR flips bits: if a cell already has Cyan and you stamp Cyan again, Cyan turns off.
Pieces rotate in 60° steps; reflections are never generated by rotation, so handed mirror pieces remain distinct.