# How to Play Gin Rummy

Written: 2023-04-17

Players: 2

Type: rummy (hand building?)

Time: 5m/hand, up to 1hr for a game


## Quick Pitch

Our favorite 2 player card game (sorry Palace).
Whether it's a couple hands over lunch or a full
game after dinner with a record on, it's perfect.
It's a nice blend of engaging (waiting for that
one card) and low effort--easy to set up and
doesn't require much thinking once you learn the
heuristics. The quick rounds mean that a bad
hand doesn't ruin the fun--your luck can always
turn!


## Goal

Be the first player to accumulate 100 points over
several rounds. Points are won each round for
swapping cards to achieve a better hand than your
opponent.


## Play

### Setup

Deal each player 10 cards, facedown. Players
may look at and sort their hands. The remainder
of the cards are placed in the middle to form
the draw pile and the top card is flipped
face up to form the discard pile.

            .----. .----.
            |////| |9   |
            |////| | <3 |
            |////| |   9|
            '----' '----'

### Gameplay

#### The Turn

Players alternate taking turns. In general, a
turn consists of picking up a card from either
the top of the discard pile or the top
of the draw pile and discarding one of
your cards from your hand (including the
recently acquired card) to maintain a 10 card
hand.

The choice of which cards to pick, hold, and
discard all comes down to trying to lower your
hand's point value.


#### Scoring

Each cards has a point value:

* Ace: 1
* 2-9: their value
* 10-K (face cards): 10

While the goal of the game is to reach 100 points,
the goal of each round is to *minimize* the points
in your hand.

At the end of the round (to be discussed soon),
the player with less points in their hand scores
the difference between their hand and their opponents
(plus any bonus points).

             .----. .----. .----.
             |3   | |5   | |8   |
             | <3 | | <> | | {> |   Player 1: 16 points
             |   3| |   5| |   8|
             '----' '----' '----'
             .----. .----. .----.
             |A   | |J   | |K   |
             | <> | | <> | | {> |   Player 2: 21 points
             |   A| |   J| |   K|
             '----' '----' '----'
           Player 1 scores 5 points
	      for the difference.

However, what makes Gin interesting is that by
combining cards you can prevent them from scoring
at all.

There are two combination types: "melds" and "runs".
Melds are 3 or 4 of a kind (the same value or face
card):

            .----. .----. .----.
            |J   | |J   | |J   |
            | <3 | | <> | | qB |
            |   J| |   J| |   J|
            '----' '----' '----'

	3 jacks are worth 0 as a meld.
	2 jacks and a king are worth 30.

Runs are straight flushes (3 or more cards of
the same suit that are adjacent in value; note that
it does not "wrap" around from King -> Ace. Aces
are low, so Ace->2->3 is a run).


            .----. .----. .----.
            |4   | |5   | |6   |
            | <3 | | <3 | | <3 |
            |   4| |   5| |   6|
            '----' '----' '----'

	4, 5, and 6 of hearts make a
	run (and are thus 0 points)


NOTE: each card can only be used in *one* combination.
For example:

      .----. .----. .----. .----. .----.
      |4   | |4   | |4   | |5   | |6   |
      | <> | | {> | | <3 | | <3 | | <3 |
      |   4| |   4| |   4| |   5| |   6|
      '----' '----' '----' '----' '----'

      Three fours and a 5 and 6 of hearts
      could either make a 3-card meld or
      a 3-card run. The "dead wood" from
      the run is lesser (4+4=8) vs the
      meld (5+6=11), so that'd be the
      preferable option. If a 7 of hearts
      appeared, the hand would be worth 0
      as the 4 could be "freed up" to be
      used in the meld.


#### Round End

There are four possible endings:

1. A player picks up a card, discards, and has
   the perfect hand of 0 points and announces "gin"

2. A player picks up a card and has all 11
   cards in a combination; they skip the
   final discard and achieve "super gin"

3. The deck runs out of cards

4. A player has < 10 points of unmatched cards
   ("dead wood") and chooses to "knock" (customary
   to literally knock on the table), ending the
   round after they discard.

In all scenarios, the player with less points in
their hand scores the delta between the hands (see
Scoring). In 1 and 2, the player with gin scores
bonus points: 25 for gin and 35 for super gin.

There are two special wrinkles to "knocking" (4):

  a. The non-knocking player may "lay off cards"

  b. If, after laying off cards, the non-knocking
     player is actually the winner, they score
     the difference as well as a 15 point bonus for
     "undercutting"

Laying off cards is a process by which the non-knocker
is allowed to take any of their cards and place them
in their opponents hand if they extend an existing
meld or run. So a player with a 4 in dead wood would
lay it off if the knocker had three 4's, netting 0
points. If, however, the knocker had one 4 and the
non-knocker had two 4's, no lay-off may occur (as
they cannot create new combinations, only extend
existing ones).

The kocker is never allowed to lay off cards, nor is
laying off cards allowed if a player goes gin (in
which case the player without gin is stuck with their
dead wood).


#### Special Rule: First Turn of a Hand

The first turn is special. The player to go
first has the option to pick up the top (and only)
card of the discard deck; should they want it, they
pick and discard and the game begins as usual.
Should they not, the other player has the option
to pick it as well. Neither player may instead
pick from the draw pile. Should the second player
pass as well, the first player begins by picking
from the draw pile. In this way, the first player
gets the "rights" to the first card, but neither
player may draw from the draw pile until both pass
up on the face up card.

Players alternate who goes first, as this option
to pick up the card is usually a slight advantage.


## General Strategy

There's a lot of good strategy with Gin. But it
really comes down to a "feel". Depending on your
opponent and how long the game has been going,
it may be wise to knock aggressively (as soon
as you dip below the 10 point threshold). The
longer the game has gone, the better you can
expect your opponents hand to be (and therefore
the more risk of an undercut). However, the
15 point undercut loss is less than a 25 point
gin bonus, so if you think they're close to gin
and you feel good about your dead wood, it may
be a worthwhile knock.

While lower cards carry less risk in that they
provide little dead wood if unmatched, they're
also much less likely to be discarded (for that
reason). Starting with 2 kings might seem like
a lot of dead wood, but remember your opponent
is highly likely to discard any king they find
(versus with two aces your only chance at a meld
is picking up a third yourself).

For similar reasons, it's wise to knock when
you feel gin is unlikely to be reached; having
two aces will be very hard to match. If you
find yourself having to give up discard low
cards that your opponent will benefit from,
it might be time to knock (i.e. trading a 2
for a 5 that'll extend a meld--you lower your
deadwood by 2 but may be giving your opponent
the card they've been waiting for!).

Lastly it's all a game of memory and odds.
Keep track of what's been discarded already,
as it may change whether you're able to make
a run or meld. If you can, watch what your
opponent grabs from the face-up pile too.
If they grab two jacks, it's a safe bet they
have a meld--it might even be worth the risk
of holding a jack in your hand: discarding
it would only add to their meld, but if they
knock you can lay it off into the meld you
know they have (this backfires of course if
you get stuck with it due to their gin).

And of course, have fun! Don't get too beat
up over a bad hand. Sometimes the cards just
aren't in your favor.

Oh and shuffle the deck thoroughly (7 times)
between rounds--playing gin is a great way
to sort a deck :)