Maddening Mazes Postcards - Dover Postcards Author:Dover These bold black-and-white mazes pop, jump, recede, advance, and shimmer with optical illusions and 3-D effects. A dozen different postcard puzzles by a noted maze master include spinning spirals, eccentric circles, wavering squares, and other challenges. Brief instructions and directions to the online solutions appear on the reverse side of eac... more »h card.« less