The theme of The Great Divide is a notably bizarre one: one player is the "West" and the other the "East," and they are competing to have as much as possible of the Rocky Mountain region drain to one side of the continental divide or the other. But of course, the themes of Euro-style games are basically irrelevant to gameplay, and so it is here: what The Great Divide actually is, is a highly original game of abstract strategy.
A 7x10 "long grain" hexagonal map containing 66 hexes is divided into six regions: the hex columns at left and right are "West" and "East," while the intervening area is divided laterally into four regions of 10 or 9 hexes each. 66 playing pieces -- one for each hex, and each containing the color of one region along with an arrow -- are placed in a cup, along with one additional playing piece, marked "5". The basic gameplay is: during your turn, draw one piece, and place it on the boad. It must be placed in the region of the same color at the piece, and you may place it with the arrow pointing in any direction. The direction indicates the "flow" of the river in this hex. Your objective: to ensure that the rivers leading off your board edge (East or West) at the end of the game drain more hexes than the rivers leading off your opponent's board edge.
Some additional simple rules ensure that pieces cannot be played to create impossible "rivers" (ones that run in circles, say, or that run into each other).
As a means of reducing the game's random element, each player has a set of cards with differing combinations of area symbols on them. Before you draw a playing piece from the cup, you may turn some of your cards to the "passive" side. This means that if you draw a corresponding piece, you pass it to your opponent to place, then draw again. This may seem paradoxical at first -- why would you want to "help" your opponent -- until you realize that, toward the end game, getting a piece for a particular region may be absolutely vital to you, that the right piece might ensure your control of a huge river.
As for the playing piece marked "5" -- the player who draws it may keep it, for 5 victory points, or pass it to his opponent and draw again. Toward the end-game, a river piece might, properly placed, earn you more than 5 points, of course.
The problem with simple abstract strategy games is that they often produce degenerate strategies. Hex is a good example; it's solved for an up to nine-by-nine board, and there's really no variety in adoptable strategy, and scant reason to play it more than a handful of times.
When opponents are wholly symmetrical, to avoid a degenerate game, you need to break that symmetry quickly. One way is to provide a game with the strategic depth of Chess; after one round, the players have moved different pawns, opening up different lines of attack, and symmetry is broken. Another is to introduce a random element, as The Great Divide does -- and yet a third is to introduce some additional elements that increase asymmetry. The cards here are one mechanism for doing so, and so is the "5" piece.
A couple of "advanced" rules add some additional asymmetrical elements, and are worth using once you're familiar with the system.
Despite The Great Divide's simplicity of system, by the end-game, you are pondering each move carefully, and worrying about which cards to flip; it's a game of surprising strategic depth, in other words. And, not incidentally, a surprising game to find in the catalog of a company that normally publishes board wargames.
