The British 21, where the banker's seat is worth winning.
The British ancestor of blackjack. The rules look similar and play quite differently, mostly because the banker's cards stay hidden and the banker's seat can change hands.
Aces are 1 or 11, court cards are 10, everything else counts its face value.
The banker deals one card face down to everyone including themselves. Players look and stake. A second card follows, again face down. Nothing the banker holds is ever shown until the end.
A pontoon is an ace with a ten-value card, and it beats everything. A five card trick is any five cards totalling 21 or less, and it beats everything except a pontoon.
Buy: increase your stake and take a card face down. Twist: take a card face up without increasing the stake. Once you twist you may not buy again. Stick: stop. You may only stick on 15 or more.
The banker then plays their own hand and turns it over. The banker wins ties, which is where the seat's advantage lies. A pontoon or a five card trick pays double.
A player dealt a pontoon takes over the bank at the end of the hand, unless the banker had one too. That is what makes the game a contest rather than a house game.