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coin game

v0.1

A surprisingly amusing and simple 2-player game my girlfriend and I invented on a date.

imprecise description

One of you is heads, the other tails. Set out 4 dimes in a square; this is the goal. You both start with 2 quarters each, flipped to your corresponding faces. Take turns flicking quarters into the goal, but hit any dimes and you lose! Whenever a coin gets knocked out of the goal, it flips and goes to the corresponding player. When all the quarters are in the goal, if a majority of them are heads or tails, that player wins.

precise rules

Instructions:
  1. Place 4 smaller coins in a square about 15 cm wide on a table.
    1. The square with corners at the centers of these goal coins is the goal.
  2. One player (Heads) sits by one edge (their line) of the goal and flips the goal coins on that edge to show heads. The other player (Tails) sits by the opposite edge and flips the goal coins on that edge to show tails.
  3. Heads sets 2+ score coins, showing heads, in front of them but outside the goal. Tails does the same, with their score coins showing tails.
    1. Throughout the game, Heads owns all score coins showing heads, and Tails owns all score coins showing tails.
    2. A score coin is in the goal if and only if its center is inside the goal.
    3. Whenever a coin leaves the goal, it is flipped over.
  4. The game begins.
  5. The winner of the previous game (if any, otherwise Heads) becomes the active player and attempts to take a shot.
    1. A shot begins when a coin outside the goal owned by the active player is moving while not touching the active player.
    2. The shot ends when no coins are moving.
    3. If the coin that began the shot did not enter the goal, it is flipped over.
  6. The players alternate becoming the active player.
  7. A player that becomes the active player must take a shot if they own any coins that are not in the goal. Otherwise, they are skipped.
  8. When all players are skipped in a row, the game ends, and if one player owns more coins in the goal than the other, that player wins the game. Otherwise, the outcome is a tie.
Penalties:
  1. A player who is not the active player loses the game if they touch anything on the table.
  2. The active player loses the game if they touch anything on the table during a shot.
  3. The active player loses the game if a coin in the goal moves except during a shot.
  4. The active player loses the game if a coin is flipped over, except to follow instruction 3.3.
  5. The active player loses the game if a coin they do not own enters the goal.
  6. The active player loses the game if a coin enters the goal from anywhere other than their line.
  7. The active player loses the game if a goal coin moves.
Examples:
  1. Heads flicks a coin into the goal. Tails flicks a coin into the goal, knocking the heads coin out of the goal. The heads coin flips to tails (3.3). Heads is the active player.
  2. Heads flicks a coin into the goal. Tails flicks a coin into the goal, knocking the heads coin out, but two tails coins also leave the goal. All three coins flip, so Heads now owns one more coin than before. Heads is the active player.
  3. Heads flicks a coin into the goal. Tails flicks a coin into the goal, knocking the heads coin into a goal coin. Tails loses (G).
  4. Heads is caught cheating with their finger still touching their coin as they try to slide it into the goal. Heads loses (C).
  5. Heads lets go of their coin properly while sliding it this time, but the coin stops short of the goal. The coin flips to tails (5.3). Tails is the active player.
Notes:
  1. The way I've written these rules, it's technically legal for the active player to place miscellaneous coins just barely outside the goal before taking a shot. Does this contribute to any powerful strategies? You could ban it by introducing another penalty: "H. The active player loses the game if a coin that was at any point in the goal during a shot touches a coin that was at at no point in the goal in that shot"
  2. Try allowing players to have an arsenal of coins of different shapes and masses. This is more relevant than one might think. For example, a US penny will hit a US quarter and then rebound, when another US quarter will not.
  3. Try playing without F.
  4. Try goals of different shapes and sizes.
  5. Try team games with each player by a different side of the goal.