>>719090514
3+3+3+3+2=win
3 can be 3 of a kind or a sequence like 123, 345, 678, etc and have to be the same suit.
You can only hold 13 tiles, meaning you can't hold onto a win when you draw the 14th tile.
And if you throw it away, you can't win later at all unless you change you winning tile(s).
Pon>taking someone else's tile to finish a 3 of a kind (has priority over Chii)
Chii>taking the person to your left's tile to finish a sequence
Kan>You turn a 3 of a kind into a 4 of a kind and reveal a tile in the Indicator wall, which shows you 1 tile nobody can draw and also tells you "the next tile in sequence is worth extra points" This counts as a 3 of a kind for winning purposes.
Kita>(3-player only, turns a North into points and draws a new tile)
Riichii>You are claiming you can win with 1 more tile and you have no called anyone else's tiles (a Kan with 4 from in-hand is safe for Riichii), this is the most common win condition
In order to actually win, you have to meet one of many "win conditions."
There are other rules building on this, but that's the core.