Object
The object is to get one of your animals into the enemy's den. You win when your opponent cannot stop you from entering his den on the following turn.

Movement
The pieces move one square at a time in any non-diagonal direction. The lion and tiger can also leap in a straight line across the river, or from bridge to bridge. An animal cannot enter its own den, and no animal except the rat can enter the water. A rat in the water blocks the leap of a lion or tiger (whether friendly or enemy) along its rank or file.

Capture
A piece can capture any other piece that has the same or a smaller number, by moving onto the same square. An exception is that the elephant is weaker than the rat, because the rat can kill the elephant by running into its ear and gnawing its brain. However, the rat cannot attack the elephant from the water.
An animal in an enemy pitfall can be captured by any other animal. Otherwise pitfalls do not affect movement or capture.
The rat can attack the enemy rat from the water, though it cannot capture the elephant in this way.

Drawn games
A situation often arises where a player has a single piece guarding a pitfall that is threatened by a stronger enemy piece. The attacker can end up chasing the defending piece back and forth endlessly, with a constant threat to the den. This manoeuvre is somewhat like perpetual check in chess. In the event that a position does keep repeating itself, you can declare a draw and start a new game.