Open lead in a variant of Spades, where players must play a winner if able (CallBreak)

Question

CallBreak is an Indian variant of Spades, The rules differences from normal Spades are:

1. Solo (no partnerships)
2. Possible bids are from 1 to 8 (no Nil bids)
3. Players must play a stronger card than the current trick winner, if able.
4. Can lead first trick with a spade (No “spades broken” rule).
5. No bags penalty.
6. Game ends after 5 rounds.

My question is, what is a strong open lead in CallBreak?

While this question could be seen as opinion based, it is not so since I have access to a simulator of the game which allows me to compare clones of the same AI-agent that differ solely in the open lead, thus finding which open lead is better.

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It is available to play in many mobile game applications and also at http://callbreak.com/.

Answer 1

I made several AI agents that plays CallBreak. My current strongest rule-based agent uses the following lead:

1. If starting with 5+ spades, lead them: lead boss, otherwise lead lowest.
2. Lead sidesuit Boss.
3. Lead strongest below the second-Boss from sidesuit with a second boss.
4. Lead low from Short sidesuit.
5. Lead Trash - low from worst suit.

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Terminology:

• Lead - the first card in the trick.
• Open lead - the lead in the first trick of the round.
• Boss - Strongest card in the suit, based on the cards that were already played. For example, the King is the Boss if the Ace was played.