RKC 满贯答叫 - folksbridge21/system2 GitHub Wiki

Roman Key Card Blackwood (RKCB)　
RKCB is a 4NT bid that, unlike regular Blackwood, asks for "key cards" instead of Aces. There are always 5 key cards.

The 4 Aces plus the King of the agreed trump suit.
If no trump suit has been clearly agreed, the King of the most recently bid suit is typically counted as the 5th key card.

在将牌同意后，用4NT问关键张：答叫如下 （1430）：

5C: 1 or 4 key cards
5D: 0 or 3 key cards
5H: 2 or 5 key cards, 无将牌Q
5S: 2 or 5 key cards, 有将牌Q
5NT:有偶数个关键张和一个缺门。 An even number of key cards plus an unspecified void
6x (any suit): 有奇数个关键张和一个缺门。 An odd number of key cards with a void.

如果6X套低于将牌，所叫套就是缺门。 If 6x is below 6 of the agreed suit then the void is in the suit bid.
如果6X套是将牌，那么就有一个高于将牌的缺门。 If 6x is a bid in the agreed suit then the void is in an unspecified higher-ranking suit.
1H-4H-4NT-6C： C缺门， 1H-4H-4NT-6H: 黑桃缺门

5C/5D答控制后，接力叫品是问将牌Q: After the 5C and 5D responses, the 4NT bidder can bid the next non-signoff step to further ask for the Queen of the trump suit. Here are the possible answers.

叫回最低阶将牌是没有将牌Q。
叫新花是有将牌Q并且所叫花色有K。
叫5NT有将牌Q，没有低于将牌花色上的K。
1H-4H-4NT-5C-5D-5S: 有红心Q和SK, 1H-4H-4NT-5C-5D-5NT, 有红心Q，没有边花K。 1H-4H-4NT-5C-5D-5H, 没有红心Q.

5C/5D/5H/5S答控制后，5NT是问特定的K，表明有5个关键张和将牌Q（或者联手10张将牌），有大满贯兴趣。答叫如下：

在六阶叫低于将牌的新花，表明有K，有多个K，从最低级花色叫起。问K者接着叫下一花色，是问此花色是否有K

1S-4S-4NT-5C-5NT-6C-6D, 6D是问同伴是不是还有DK, 有就叫大满贯。 1S-4S-4NT-5S-6C, 关键张齐全，问搭档梅花是不是有Q， 有就叫大满贯 没有K叫回六阶将牌 （也可能有K高于将牌花色）

Note: The RKCB partner is entitled to bid a grand slam if he thinks that 13 tricks are available.