Related Openings
Four knights - Belgrade gambit	e4, e5, Nf3, Nc6, Nc3, Nf6, d4, exd4, Nd5
Four knights - Scotch, 4...exd4	e4, e5, Nf3, Nc6, Nc3, Nf6, d4, exd4
Four knights - Scotch, Krause Variation	e4, e5, Nf3, Nc6, Nc3, Nf6, d4, Bb4, Nxe5