Sabin Rains is a flipping game played on a hex board, in which the flipping occurs along "hex rings." A hex ring is the ring of six spaces surrounding any one space on the board. The specific rules are:
 
Take turns placing pieces on the board. A piece may not be placed in a space that is surrounded on all sides (the "plug rule"). When a piece is placed, it flips all enemy pieces that are sandwiched between itself and a friendly piece along a hex ring. When five enemy pieces are located on a hex ring, a single piece dropped in the remaining space will flip all five pieces.
 
The player with the most pieces on the board when there are no further moves is the winner. In the illustration below, blue has won because there are no further moves and blue has the most pieces on the board.
 
Sabin Rains comes in two board sizes, one with five hexes to a side, the other with six.