Patent US 4,687,207

A board game has sixteen playing pieces, arranged on a playing surface, in four rows and four columns. Each playing piece has a mark which is made visible by selectively orientating the piece. Players take turns orientating pieces. A point is scored each time four marks are arranged in a pattern corresponding to four of the numbers in Durer's magic square whose total is 34. The players can also rearrange the pieces by interchanging entire rows or columns in a manner which would not alter the corresponding property of Durer's square wherein corresponding rearrangements of Durer's numbers would still result in a sum of 34. A scoring sheet, indicating scoring patterns, can be used to keep score.