Byzantine Blackwood convention Byzantine Blackwood convention Byzantine Blackwood is a bidding in the game of bridge. Devised by Jack Marx, it is a complex version of the (by which a four notrump (4NT) asks about 's holdings). Its premise is that both aces and kings may safely be shown in response to a Blackwood-type 4NT enquiry; provided that such kings are in well-defined "key" or "half-key" suits, there being no more than two such suits. The name was chosen to express the idea that Byzantine Blackwood is a development from Roman Blackwood, by analogy with the Byzantine Empire and the Roman Empire; rather
Chess tactic would prefer to pass and make no move, but a move has to be made, all of which weaken his position. Situations involving zugzwang occur uncommonly, but when they do occur, it is almost always in the endgame, where there are fewer choices of available moves. "Zwischenzug" (German for "intermediate move") is a common tactic in which a player under threat, instead of directly countering, introduces an even more devastating threat. The tactic often involves a new attack against the opponent's queen or king. The opponent then may be forced to address the new threat, abandoning the earlier attack. The