If you enjoy number puzzles where every row and column uses a digit once and arithmetic cages narrow the possibilities, PUZRU should feel approachable immediately. The core board is 6×6 and uses the digits 1–6 once in each row and column.
What will feel familiar
- Every cell is constrained by both its row and its column.
- Connected cages restrict which values can fit together.
- Candidate elimination becomes stronger when arithmetic and placement logic intersect.
What changes in PUZRU?
PUZRU uses addition-only cage totals rather than a mix of arithmetic operators. More importantly, every live player receives the same current puzzle. The first verified solution becomes the Discoverer, a short contribution window follows, and six solved positions carry into the next generated puzzle.
Why addition-only works
Removing operator switching reduces rule overhead on a phone without removing the interaction between cage combinations and Latin-square constraints. The difficulty comes from how those constraints cross the grid and from the quality-gated no-guess solve path.
What changes in practice?
Put the idea into practice
The fastest way to understand the interaction between row, column and cage constraints is to solve a board. Start in the 200-puzzle progressive Training Room, then enter the live world whenever you are ready to race for Discoverer.