CodeMaster

Your opponent has secretly filled in his Secret Code Grid. You have done the same. You ask him questions about his Grid, while trying to reveal little about your own. Can you duplicate his Code--before he unravels yours?

It will require strategy and cunning--and a dose of logical reasoning!

Then match wits with your opponent Super-CodeMaster, using any of the eighteen Grids that come with the game. Or play it by yourself, using the Solitaire Booklet also included. Either way, it's exciting, unique and challenging.

By the makers of the puzzle, LogicMaster.

—description from the back of the box

Each player takes a Grid Sheet (a sheet of two empty 25-square grids). On the top grid each writes his secret code. This consists of the letters A through E, each written five times. Write one letter in each square. The same letter may not appear more than one In a row or in a column. Therefore every row and column will contain each of the five letters.

You must discover your opponents secret code by using sums (made from the addition of the row and column numbers containing that letter) and knowing whether the letters in two named spaces are the same or different.

—user summary