had a game idea: sandcastles.

originally i thought of using d10s for this, but it might be most convenient to use a deck of playing cards.

at the beginning of the game, each player draws five cards. they can chose to discard and redraw any number of the cards first drawn. after deciding on cards, each player must arrange them into a ‘board’. once arranged, each card (except the last) is scored as follows:

• if a card has the same value as the card to its right, 3 points are awarded
• if a card has value one greater than the card to its right, 2 points are awarded.
• if a card has a lesser value than the card to its right, 1 point is awarded.
• if a card has a greater value than the card to its right, no points are awarded

in brief:

• a=b → 3
• a+1=b → 2
• a
• a>b → 0

(note: if you play with d10s instead of cards, matches should only award 2 points)

at the start of each round, calculate the score of each board. players can be in three positions: the lead, the last, and the rest.

• if no players has more points than you, you are in the lead.
• if no player has less points than you, you are in the last.
• if you are not in the lead or the last, you are in the rest.
• cards will be first draw face‍-​down. the lead draws two cards. the rest draws one card. the last may chose to sacrifice one card from their board, and draw one card and immediately turn it face up.

rounds have two phases.

in the first phase, players take turns. players of greater score go before players of lesser score.

for each card drawn this turn, a player may chose to attack or build. if attacking, they first must declare where they are attacking, pointing to a card on some player’s board.

once every player has decided, the first phase ends.

next, attacks are resolved. the attacking card is turned face up and compared to the target. if it is equal to the target, the attack has no effect. if it is greater than the target, the target card is discarded, and the card to its left is attacked.

if it is less than the target, but greater than some other card on the board, the lowest, leftmost such card is attacked. (this will also occur if the card you were attacking has been already been discarded)

once every attack is resolved, players who chose to build may insert a card into their board at any position.

this ends the round.

at the end of the round, if you have no cards on your board, you lose. if you are attacked when your board has no cards, you lose.

if you have ten or more cards, you win.

if there is more than one winner, everyone else loses, and the game continues until there is only one winner.

if this round you attacked a player who lost, draw an extra card next round