XYZ is a convention whereby the first 3 bids of a partnership's auction are on the 1-level (but not 1NT- over 1NT you can play some version of New Minor Forcing). SO, it goes 1-something, 1-something, then 1-of-a-major. After those 3 bids (1X-1Y-1Z), the typical treatment is to use:
2
by responder as an artificial relay. Opener must bid 2![]()
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