Thirteen

Objective
The objective of the game is to be the first player to get rid of all your cards.

Deck, card and suit rank
The game is played with a standard 52 card deck. The rank of cards from low to high is:

3 4 5 6 7 8 9 10 Jack Queen King Ace 2

The unusual thing here is that the 2 is the highest card. It's also a special card in that it cannot be used in any sequences.

The suits also have a rank. The suits from low to high are:

Spades♠, Clubs♣, Diamonds♦, Hearts♥

The suit rank is less important than the normal card rank though, and only comes into effect if you have two cards with the same rank. E.g. a 5 of spades is always higher than a 4 of hearts, even though spades is the lowest suit and hearts is the highest suit, because 5 is higher than 4 and that's more important. But if you have a 5 of spades and a 5 of hearts then the 5 of hearts would be considered higher because the rank is the same but hearts is higher than spades.

Gameplay
In real life there can be 2 or more players in the game, but we always have 4 players. Each player gets dealt 13 cards. The player with the 3 of spades starts the first round of the game. He has to play that card first, but it can be part of a combination. In later rounds the winner of the last round starts and doesn't have to start with the 3 of spades.

When the table is empty and a player is playing he can play a few different types of combinations. Those are:

Single card. Just a single card of any rank.
Pair of cards with the same rank, e.g. two 3's.
Three cards of the same rank.
Four cards of the same rank.
Sequence of at least 3 cards, e.g. 4,5,6. The card in a sequence don't have to have the same suit. A 2 can never be part of a sequence.
Double sequence of at least 6 cards. A double sequence has two cards of each rank, e.g. 3,3,4,4,5,5. These are hard to get and don't often occur.
Once a player has put out a combination the other players have to try to play the same type of combination with a higher rank. E.g. if the first player puts out a single card, a 5 lets say, then the other players can only put out single cards on top of it. If the first player puts out a pair of cards the others must also put out a pair, with a higher rank. If a player can't play a higher ranking combination of the same type he must say Pass. If no player can put out a higher combination than what's on the table, they all say Pass and the cards are removed from the table. The player who had the final combination on the table gets to play next and can play any combination he wants, since the table is now empty.

A player is allowed to Pass even if he has cards that he could play. However, if he does that he will have to keep passing until the current cards have been cleared from the table.

Understanding the ranking and how it works is very important. We talked about the suit rank before, e.g. a ♥5 is higher than a ♣5, and so you can play the ♥5 on top of the ♣5.

For pairs you can play the same numerical rank if the highest card of the pair is higher than the highest card of the pair on the table. So you can can play ♣5♥5 on top of ♦5♠5 because ♥5 is higher than ♦5. Or you can play any pair of 6's or higher on top of any pair of 5's because numerical rank matters more than suit rank.

For sequences you can play another sequence if the highest card of your sequence is higher than the highest card of the sequence on the table. Again, it's all about the highest card of the combination. So you can play ♣5♥6♦7 on top of ♦5♦6♣7 because ♦7 is higher than ♣7. Or you can play any three card sequence that starts on a higher numerical rank, e.g. starts from 6.

It sounds more complicated than it is. Basically you always have to play the same type of combination as the one that's on the table and the highest card in your combination has to be higher than the highest card in the combination on the table.

Bombs
2 is the highest card in the deck. However, there are a couple of combinations known as bombs that can be played on top of 2's as follows:

A 4-of-a-kind or a double sequence of 3 or more can be played on top of a single 2.
A double sequence of 4 or more can be played on top of two 2's.
A double sequence of 5 or more can be played on top of three 2s.
A higher bomb of the same type of combination can be played on top of a previously played bomb.