A game of tavla ends when one player has borne off all checkers. If the losing side has not borne off a single checker by then, the game ends with a mars (gammon) and the winner scores 2 points.
Example
At 3-1 a mars makes it 5-1 and the match ends. Without a mars the same game would only be worth 1 point.
Tip
Bring your runners home quickly to keep your opponent from bearing off.