Two Eggs

Designed and made by D. Namdarian 2013; sleeve added by J. Storer.
(made from 1/8" thick laser cut plastic, board 2 layers, pieces 2 layers, 4.3" x 5.5" x 3/8")

The top layer has a blue egg on the left and a green egg on the right, each formed from three sections, arranged as two curved pieces side by side each occupying a 2 high by 1 wide space, sitting on top of a curved piece that occupies a 1 high by 2 wide space. The goal is to exchange the two eggs. Each of the six of the top layer egg sections occupies a 2 unit region of the top layer and has one of its halves glued to a 1x1 white piece on the bottom layer. The remainder of the bottom layer consists of 5 free moving 1x1 white pieces and one empty 1x1 region. As the pieces slide, portions of the top layer may slide over the free 1x1 pieces on the bottom layer. They may also slide over the rim of the puzzle. So although the board is based on a 3 by 4 grid, the top layer moves around what is effectively a 5 by 6 grid.

The following pages show the solution sheet that came with the puzzle which presents a 78 move solution. The moves of the free 1x1 pieces on the bottom layer can be achieved by pushing on the exposed portion of the piece or combining two moves by pushing on the top layer and dragging a 1x1 free piece below, with the exception of Moves 10 and 18. Move 10 can be overcome by combining Moves 10 and 11 so that the piece of Move 11 pushes the piece of Move 10 as it moves. Move 18 may require one to cheat just a little by lifting the blue egg section that covers the free 1x1 piece below it in the bottom row.

On the following pages, after the puzzle solution sheet, is shown a different sequence of moves that can be taken after move 58 to lead to a shorter solution of 74 moves.

It seems reasonable that when a top layer piece covers a free moving bottom 1x1 square that the two can move together to count as one move, in which case the solution sheet sequence can combine moves 4+4, 6+7, 13+14, 29+30, 34+35, 46+47, 48+49, 50+51, 62+63, 74+75, to reduce the total move count from 79 to 69. Or, the 74 move solution can combine moves 4+4, 6+7, 13+14, 29+30, 34+35, 46+47, 48+49, 50+51, 62+63, 72+73, to reduce the total to 64 moves.

Puzzle Solution Sheet, Page 1

Puzzle Solution Sheet, Page 2

Puzzle Solution Sheet, Page 3

Puzzle Solution Sheet, Page 4

Puzzle Solution Sheet, Page 5

Puzzle Solution Sheet, Page 6

Puzzle Solution Sheet, Page 7

Shorter Solution From Position 58, Page 1
(figure graphics copyright and courtesy of D. Namdarian)

Shorter Solution From Position 58, Page 2