The rules of Tien Len
Two to four players, each for themselves, thirteen cards each from a pack of 52; with fewer than four, the rest of the pack stays out. The threes are lowest and the twos highest: 3 4 5 6 7 8 9 10 J Q K A 2. Between two cards of one rank the suit decides, spades lowest, then clubs, diamonds and hearts, so the 3♠ is the lowest card in the pack and the 2♥ the highest.
Whoever holds the lowest card dealt leads the first hand of the game, and the first play has to include it: the 3♠ at a table of four. After that, the first player out of the last hand leads, anything at all.
You may play one card, a pair, three of a kind, four of a kind, a run of three or more cards in a row (in any suits, from three up to ace), or a run of three or more pairs in a row. A two is never in a run. Each player in turn beats what is on the table with the same kind and as many cards, higher, or passes. A play is as high as its highest card: rank, then suit.
The twos have their own answers, the bombs. A run of three pairs beats a single two; four of a kind beats a single two, a pair of twos or a run of three pairs; a run of four pairs beats all of those. Three twos have no answer.
A pass is for the rest of the round, unless the table plays it as being for that turn only. When everybody else still holding cards has passed, the round goes to whoever played last: the table is cleared and they lead again. If that play was their last card, the next player still holding cards leads.
A player who plays their last card is out, and the hand goes on until only one is left holding cards. The places score: at a table of four, 3 for the first out, 2 for the second, 1 for the third and nothing for the last; at three, 2, 1 and 0; at two, 1 and 0. Once anybody's total reaches the target, 10 unless the table chose 5 or 20, the game is over and the highest total wins.
Unless the table turned it off, a hand dealt all four twos, a dragon (one card of every rank from three to ace), six pairs, or five pairs in a run wins at once: its holder scores first place, and nobody else scores.