411 REFERENCE · Wikibooks
Chess Opening Theory/1. c4/1...e6/2. Nf3/2...d5/3. Nc3/3...dxc4/4. d3/4...cxd3/5. Bg5
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White sets up a trap.
Opening table
c4 e6 nf3 d4 nc6 dxc4 d3 cxd3 Bg5