Obsession is a board game for two players in which one player wins by moving his ten rings along ten slots.
He must get all ten rings into the "Safety Zone" before his opponent.
Each player rolls a pair of dice, and can move a number of rings given by the sum of the two dice.
He choose either to move their own rings up, or their opponents rings down.
The two players take place on the opposite sides of the iPad screen.
In the middle of the screen a board is shown with two symmetrical zones, one for each player.
In each zone there is a set of 10 long oval slots, and a second set of 10 small circular slots. The last set is the Safety Zone.
On each zone, a set of rings is also shown: the red ones are owned by player 1, and the white ones by player 2. All the rings are initially in the start position.
When the turn of a player comes, he can see a red and white button on his side of the screen, and he should touch it.
Two dice start rolling at this point. When they stop, the number of available moves is given by the sum of the two dice.
A line of white dots is also shown on the players side, indicating the number of available moves.
The player can now start touching rings to move them.
Touching one of his rings, he will move it from the start to the advanced position, or from the advanced position to his Safety Zone.
Touching one of the adversarys rings in the advanced position, he will move it back to the base position.
Normally a player can only move a given ring once at each turn. But, in order to prevent stalling situations, when all the possible move are exhausted and the player has more available moves, then he will be allowed to move again a ring already moved in the same turn.
Rings on the Safety Zone cannot be moved back.
At each move, the number of residual available moves is decreased. The line of white dots will be updated consequently.
When all the available moves are done, the turn passes to the other player.
The game ends when one player puts all of his rings in the Safety Zone.