>>1108972It's not that hard.
You need a pre-determined combination of tiles forming 3 triplets and a pair to be able to win (depending on certain conditions this may change) - those are called Yaku.
You If you don't have one, you can't win.
The most commons are:
-Concealed Hand (Riichi, i.e. 3 triplets and a pair, without having called your opponent's discards to complete a triplet).
-All-Simples (TanYao, which means nothing but tiles numbered 2 to 8, not extremity tiles, no winds, no dragons),
-Honor triplet (Yakuhai, having a dragon triplet, our a triplet either of the seat wind or round wind).
-All Triplets (Toitoi/Sanakou, Have all triplets, either calling/not calling)
-Seven Pairs (Chiitoitsu, self-explanotory, you need 7 pairs of any tiles, hand will be concealed).
-Full Sequence (Ittsu, have a sequence 1,2,3,4,5,6,7,8,9 regardless of suite, bonus if they're the same).
I made yout of Novice on MajSoul only knowing Riichi, TanYao and Yakuhai.
If you discard a tile and you need one of the same tile later to declare a win, you can only win by drawing that tile instead of calling one of your opponent's discards. That's called Furiten. So beware of your discards.
The rest you get by playing and studying the game as you go.