Tennis (paper game)  Tennis is an (abstract) strategic pencil and paper game for two players. The game field consists of 4 fields and a centre line. These are called (-2,-1,0,1,2), with negative numbers belonging to player 1, positive to player 2. At start, the ball is at the centre line (0). Both players start with the same initial number (e.g. 50 points). In each draw, both players choose a number, and the ball is moved towards the player with the smallest number. The number that was chosen reduces the points for the next draws. The aim of the game is to move the ball beyond the second field of the opponent. The game is described in. For a simple description, we include the numbers -3 and 3 to denote the ball being beyond the second field. This results in a playfield as (-3,-2,-1,0,1,2,3). The draw of player i at time t will be denoted as formula_1, the ball is at time t in formula_2. At start is formula_3 and for both players is formula_4. Each player chooses a whole number formula_5, with formula_6 only if formula_7. The number reduces the points of this player (formula_8). The ball is moved as follows:  For the result of the game, the following rules apply:  In the first example, player one wins, but the ball is still on the playfield when both players do not have any points left. In the second example, player 1 wins again, by hitting the ball beyond the other playfield using the last points he has left. A similar game is "Footsteps", marketed at one time as "Quo Vadis" by Invicta. Typically, players face each other at opposite ends of a "board" that is a simple row of seven spaces, with a single token initially on the center space. Each player starts with 50 points. On successive turns, each writes down a number; the players compare numbers and the player with the higher number advances the token one space toward the opponent. The winning "bet" is deducted from the winner's point total; each "bet" must be between 1 and the player's remaining points. The winner is the first to reach the space nearest the opponent—in other words, to win three more turns than the opponent. Footsteps closely resembles Tennis, but does not treat the center space as a "net" to be skipped over; each move consists of one step, never two.