Related Openings
center game - Hall Variation	e4, e5, d4, exd4, Qxd4, Nc6, Qc4
center game - Berger Variation	e4, e5, d4, exd4, Qxd4, Nc6, Qe3, Nf6
center game - l'Hermet Variation	e4, e5, d4, exd4, Qxd4, Nc6, Qe3, f5
center game - Paulsen attack	e4, e5, d4, exd4, Qxd4, Nc6, Qe3
center game	e4, e5, d4, exd4, Qxd4, Nc6