The South Asian partnership game where Jacks and Nines are the top cards: bid on four cards, choose trumps in secret, and keep them hidden until someone can't follow suit.
Twenty-Nine (29) is played by four players in two partnerships, partners sitting opposite: here you and North play against West and East. It uses 32 cards, 7 to Ace in each suit. In every suit the cards rank J, 9, A, 10, K, Q, 8, 7, and they score Jack 3, Nine 2, Ace 1 and Ten 1. That makes 28 points in the pack. Play is clockwise.
Everyone is dealt four cards. Starting left of the dealer, players bid a number from 15 to 28: how many points their side will take. Each bid must be higher than the last, or you pass, and the bidding ends when three players in a row pass after a bid. If the first three players all pass, the dealer must bid 15.
The highest bidder chooses the trump suit in secret, and everyone gets four more cards. The player to the dealer's left leads. You must follow suit if you can; if you can't, you may play any card.
The trump suit stays hidden at first, and until it's shown every trick goes to the highest card of the suit led. The first player who can't follow suit asks for trumps, and the bidder shows the suit. From that trick on, the highest trump wins. Nobody is ever obliged to play a trump.
Twenty-Nine is one of a group of South Asian trick-taking games in which the Jack and the Nine are the highest cards in every suit. Pagat.com says it is almost certain these games come from the European family of Jass games, which began in the Netherlands, and suggests they were probably brought to the Indian subcontinent by Dutch traders. Wikipedia instead says they are believed to have come with Indian South Africans, who were also influenced by the Afrikaner game of Klaverjas.
Pagat describes 29 as popular across much of northern India, including Bombay and West Bengal, and also in Bangladesh and Nepal. Wikipedia calls it the most popular variant of Twenty-eight and one of the most popular card games in South Asia, especially in Bangladesh.
The game's name comes from an extra point once given for winning the last trick, which made 29 points in all. Pagat notes that most players no longer count it, and so here the total is 28. Rules vary a great deal from place to place: these follow pagat's main description.
Twenty-Nine is a free browser version of the South Asian card game, played with a computer partner against two computer opponents, with a daily game and online leaderboards. There's nothing to download and no sign-up.