The name, and why it is Thirteen
The game is Vietnamese, and its name there is Tiến Lên — roughly “go forward”. Written without accents it becomes Tien Len, which is how most English-language sites spell it. You will also see it listed as Thirteen, 13, or just Vietnamese cards.
The number comes from the deal: four players, thirteen cards each, one standard 52-card deck used exactly. Nothing is left over and there is no stock to draw from — the hand you are dealt is the hand you play.
If you know Big Two, Dai Di or Chinese Poker, you will recognise the shape. The combinations and the ranking are different enough that they are genuinely separate games.
