In the national standard mahjong, it is the last card played by Hu Biejia. In Japanese mahjong, it is called touching the moon under the sea or fishing for the moon under the sea. It is the last card and card on the wall except the mountain card, which is equivalent to the revival of national mahjong. In Japanese mahjong, finding the moon on the sea according to the national mahjong rules is called fishing at the bottom of the river. And fishing for the moon in the sea is to add another one to the original Hu brand number.
Other Hu cards
1, Four Happiness: After playing cards, players have four identical cards in their hands, and they can Hu cards. (Four happiness points are equal to Xiao Hu's self-touching)
2. Half-board Hu: After playing cards, players don't have 2, 5 and 8 (cards), so they can Hu cards. (equivalent to Xiao Hu touching himself)
3. Lack of a color: After playing cards, players can play cards without a door in their hands. (equivalent to Xiao Hu touching himself)
4. Liu Liushun: After the card is played, the player has two engraved cards (engraved cards: three identical cards), so he can Hu cards. (equivalent to Xiao Hu touching himself)
5, Pinghu: 2, 5, 8 will do, the rest will be carved or straight or a word, you can Hu card.