A card game for 2 players
Imagine a 3×6 grid between the players, with the players at the narrow ends.
Deal a face down card into each of the 6 grid cells closest to each player, leaving the middle 6 empty.
Choose a random player to go first. That player draws 1 card, and the other player draws 2.
Play both of your cards one at a time as described below. (Except the first turn of the first player will just have one card to play.)
Draw 2 to end your turn, so you can think about your next move while your opponent takes their turn.
You can play any card face down in the 6 cells closest to you.
Red cards may be played face up in any empty cell to do damage. Hearts do damage in all four orthogonal directions (up, down, left right) and Diamonds do damage slanty.
When a face-down card is damaged it is flipped face up. When a face up card is damaged it is discarded.
After damage is resolved, any red face-up cards are discarded.
If you have cards you cannot play (e.g. black cards in the early game) discard them instead.
A player wins when they play a card that would do damage off the end of the grid towards their opponent where there would be 3 more grid cells if the board was longer.
That's enough rules for now, play the game!
Once you've played a few times with the rules above a few times, add the rules below one at a time. If you find that the games are going long enough that you need to shuffle the discarded cards then add one of the offensive optional rules below.
During setup, each player can look at the 6 cards that start on their side and decide which one goes in each of the 6 cells closest to them. No peeking after this!
Red face cards have double range (they damage in the same directions, but damage two cells out in those directions.) Note that you do not win by doing damaga that extends off the left/right sides of the board, to win you must do damage where there would be an additional cell if the board was longer towards your opponent.
Black cards can be discarded from your hand, instead of played, to flip any card face down. Also you can play black cards face up on top of any face-down cards in the 6 cells closest to you. When cards do damage, they only damage the top-most card in each cell.
When an ace is played face up or turned face up, after you are done flipping cards up from damage, remove all face-up cards from the board.
When a 2 card is played face up, or turned face up turn all cards on the board face-down. Timing is important here: This happens after damage flips cards face-up, after damage removes cards that were already face up, but before aces remove face-up cards, and before red face-up cards are removed.
You can choose to play black face cards face up in any empty cell. When a black face card is played face up or flipped face up, all cards in the cell towards the opponent (of whoever's turn it is) are discarded (don't do flipping/damage things, just directly discard them.) Note that unlike red cards, this only removes cards from the game, and thus cannot be your winning move as it doesn't cause damage.