Spades

Variant played: Spades always trump · teams · nil contract and bags · Version 1.0.0

Objective

Bid and take a set number of tricks as a team, with spades always trump.

Setup

1. 4 players in two alternating teams; 13 cards each.
2. Each player bids from 0 to 13 tricks; partners' bids are added together.
3. Nil is a bid of 0; blind nil is not enabled in the MVP.

Turn or round flow

1. The player to the dealer's left leads.
2. You must follow suit if possible; otherwise, any card, including spades, may be played.
3. The highest spade wins; without spades, the highest card of the led suit wins.
4. The winner of the trick leads the next trick.

Legal actions and obligations

• Spades cannot be led until they have been broken, unless the hand contains only spades.
• Ranks go from 2 to Ace.
• The bid is locked before the first trick.

Score

• Contract made: 10 points per bid trick + 1 per overtrick (bag).
• Contract failed: -10 points per bid trick.
• Each set of 10 bags scores -100 points and removes 10 bags.
• Successful nil: +100; failed nil: -100; the nil player's tricks count as bags/tricks for the team under the standard rule.

End of game

• A round ends after 13 tricks.
• The game ends when a team reaches 500 or drops to -200 at the end of a hand; highest score wins.

Locked special cases and variants

• If tied at the threshold, play an extra round.
• Joker, deuces high, suicide, and blind nil are disabled.

Artificial intelligence

The AI uses only its hand, public cards, the allowed history, and the legal actions sent by the server.

• Easy bids according to its Aces/Kings and plays the lowest legal card.
• Normal estimates tricks from honors, long suits, and spades, protects the partner's nil, and manages bags.
• Hard tracks the remaining high cards and adjusts its plan to the combined contract of both teams.