How to Play

Letters, not numbers

This is a standard 9×9 Sudoku — but instead of digits 1–9, you use 9 unique letters. Each letter secretly maps to a digit.

Classic Sudoku rules

Every row, every column, and every 3×3 box must contain each of the 9 letters exactly once. No repeats!

Use the letter key

A letter key is shown at the top of the puzzle — it tells you which letters are in play. Tap a cell, then tap a letter button to fill it in.

Hints & checking

Use "Check" to highlight mistakes in red, or "Reveal" if you get stuck. Mistakes are shown but not corrected automatically.

Reveal the science word

When you solve the puzzle correctly, the 9 letters rearrange to spell out a secret science word — along with its definition!