Rulehunt

Sudoku, but we won’t tell you the rule. Every board in Rulehunt is an ordinary sudoku with one extra rule hidden inside it. The board refuses any digit that breaks that rule — and every refusal is caused by a digit you can already see. Your job is not just to fill the grid. It is to work out what the rule is. HOW A HUNT GOES • Solve as far as ordinary logic takes you. • Try a digit. If the hidden rule forbids it, the board refuses — a red mark, no penalty. • Point at the visible digit you think explains the refusal. The board confirms or denies. • Test a hypothesis: light up the cells a knight’s move away, the neighbours, the diagonals, and watch which explanation fits. • Name the rule in your own words — “cells a knight’s move apart cannot hold the same digit” — and record it in your bestiary. WHAT IS IN THE BOX • Five short lessons that teach the hunt in a few minutes. • A quick daily…