AI Details – WorldWinner

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The Basics
Strategy
AI Details

In addition to studying external sources, it is best to learn the details of how the AI in Spades Showdown plays.

This will help you learn to cooperate with your partner effectively and crush your opponents.

Terminology

Set - preventing opponent’s from making their bid.
Side Suit - any suit that is not trump (Hearts, Diamonds, Spades)
Singleton - starting with only one card of a side suit.
Doubleton - starting with 2 cards of a side suit.
Void - when a player is out of a suit.
RHO, LHO - Right Hand Opponent, Left Hand Opponent (Players to the right/left of this AI)
7D, KC - Specific cards will be referred to in this format (7 of Diamonds, Queen of Clubs)
AK(x), KQ(x) - The holdings of a suit. Ace, King, and another card all of the same suit.
Ruff - Another word for trumping. Playing a spade when a side suit was led.
Cross-Ruffing - A pattern where you and your partner pass back and forth ruffs. If you are out of diamonds, and your partner is out of hearts, you lead hearts, they trump, and lead back diamonds to you. This can be a very effective strategy for taking a lot of tricks and setting the opposing team.
Hi-Low Signal - A type of signal where you play the higher of 2 cards first, when it would otherwise be logical to play the lower card. More details below.

The AI is not designed to be “elite”, to allow a wide range of players to be effective against them. So, some strategies outlined here are known to be lacking/less than optimal.

General Motives

1. (These will be displayed when there isn’t a more specific option available).
  1. "My only legal move.”
  2. "Going nil!"
  3. "Covering nil."
  4. "Preventing nil."
  5. "Trying to make our bid."
  6. "Trying to set them!"
    1. The AI will try to set opponents when the table bid is 12 or more, or when the table bid is 11 and the opponents bid high. Otherwise, it will try to avoid bags.
    2. If someone goes nil, the AI will frequently decide it’s better to try to set the non-nil player than prevent the nil bid.
  7. "Avoiding / giving bags."
    The AI will try to avoid additional bags once their team has made their bid, they have been set, or they have successfully set the opposing team.

Leads

1. 1. 1. (These are listed in order of preference. So, the AI will try to do this first, if it cannot, it will proceed down the list. These are for standard bids, where no player went NIL).
      1. "Leading a winning sequence."
        
        Leading one card from AK(x) to try to lock up a trick before switching to cross-ruffing. It will lead the K from this sequence.
      2. "Leading my singleton.”
      3. "Leading my doubleton."
        
        AI will not lead from a K(x) doubleton, hoping to save and win with the K later.
      4. "Leading high sequence."
        
        The AI will lead from a strong sequence in a side suit (excluding AK(x), which were covered above)
        
        AQJ -> Leads Q
        
        KQJ -> Leads K
        
        KQ -> Leads K
        
        QJ10 -> Leads J
      5. "Leading a suit my partner is out of."
        
        Leading low cards from a suit that their partner is void in to set up a ruff, as long as RHO is not also void.
      6. "Leading my partner's initial lead."
        
        The AI will remember your initial lead and give it back to you. So, if you have AK(x), you can lead one of them, and switch to dumping your singleton/doubleton. The AI will do the same, and you can lead back their initial lead to them
      7. Leading Spades
        
        If it has more than the average number of spades and wants to bleed them from opponents.
      8. "Leading highest of suit."
        
        The AI knows this card is the highest remaining card in that suit. (Example, QD after AD and KD have already come out)
      9. "I don't have a good lead..."
        
        No great options, so giving up the lead.

Playing Second

1. "Trying to win this early."
  1. If the AI was planning to lead this suit, or if it has most of the higher cards, it will try to take this trick, assuming its partner cannot, and that the leader is short in that suit.
2. "Playing hi-low to signal to my partner."
  1. If the AI had a non-king doubleton in this suit, it will play the higher of its two cards. Once you see the second card come from this AI out of order, it signals to you that it is out of that suit, so you can start to cross-ruff earlier.
3. "Playing second hand low."
  1. The AI will play “second hand low”, even if it has a higher card. This saves medium cards for later, and allows their partner an opportunity to win the trick cheaply

Playing Third/Fourth

1. There are no dedicated “Shouts” for these positions, but play will follow these general strategies.
2. From 3rd position, will generally play “3rd Hand High”, referring to the practice of playing the highest card it has to win the trick or deny the 4th player from winning cheaply. This can have the side effect of promoting their partner's card.
3. From 4th position, will try to win the lowest winner available.
4. Will play over their partner only if they were unlikely to win, or if they are avoiding bags.
  If playing under another player, they will try to initiate a Hi-Low signal if they have a non-king doubleton in that suit.

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