ECO B21
ECO B00–B99 — Semi-Open Games other than the French: 1.e4 answered by the Sicilian, Caro-Kann, Scandinavian, Alekhine, Pirc and more.
32 named opening lines are classified under ECO code B21.
- Bird Opening: Dutch Variation, Batavo Gambit — 1.e4 c5 2.f4 d5 3.Nf3 dxe4
- Sicilian Defense: Coles Sicilian Gambit — 1.e4 c5 2.d4 cxd4 3.Qxd4 Nc6 4.Qd1 Nf6 5.Bc4
- Sicilian Defense: Halasz Gambit — 1.e4 c5 2.d4 cxd4 3.f4
- Sicilian Defense: McDonnell Attack — 1.e4 c5 2.f4
- Sicilian Defense: McDonnell Attack, Tal Gambit — 1.e4 c5 2.f4 d5 3.exd5 Nf6
- Sicilian Defense: McDonnell Attack, Toilet Variation — 1.e4 c5 2.f4 d5 3.Nc3
- Sicilian Defense: Morphy Gambit — 1.e4 c5 2.d4 cxd4 3.Nf3
- Sicilian Defense: Morphy Gambit, Andreaschek Gambit — 1.e4 c5 2.d4 cxd4 3.Nf3 e5 4.c3
- Sicilian Defense: Smith-Morra Gambit — 1.e4 c5 2.d4
- Sicilian Defense: Smith-Morra Gambit Accepted — 1.e4 c5 2.d4 cxd4 3.c3 dxc3
- Sicilian Defense: Smith-Morra Gambit Accepted, Chicago Defense — 1.e4 c5 2.d4 cxd4 3.c3 dxc3 4.Nxc3 d6 5.Nf3 e6 6.Bc4 Nf6 7.O-O a6
- Sicilian Defense: Smith-Morra Gambit Accepted, Classical Formation — 1.e4 c5 2.d4 cxd4 3.c3 dxc3 4.Nxc3 Nc6 5.Nf3 d6 6.Bc4 a6 7.O-O Nf6
- Sicilian Defense: Smith-Morra Gambit Accepted, Danish Variation — 1.e4 c5 2.d4 cxd4 3.c3 dxc3 4.Nf3
- Sicilian Defense: Smith-Morra Gambit Accepted, Fianchetto Defense — 1.e4 c5 2.d4 cxd4 3.c3 dxc3 4.Nxc3 Nc6 5.Nf3 g6
- Sicilian Defense: Smith-Morra Gambit Accepted, Finegold Defense — 1.e4 c5 2.d4 cxd4 3.c3 dxc3 4.Nxc3 e6 5.Nf3 d6 6.Bc4 a6 7.O-O Be7 8.Qe2 Nf6
- Sicilian Defense: Smith-Morra Gambit Accepted, Kan Formation — 1.e4 c5 2.d4 cxd4 3.c3 dxc3 4.Nxc3 e6 5.Nf3 a6
- Sicilian Defense: Smith-Morra Gambit Accepted, Larsen Defense — 1.e4 c5 2.d4 cxd4 3.c3 dxc3 4.Nxc3 Nc6 5.Nf3 e6 6.Bc4 Qc7 7.Qe2 a6 8.O-O Bd6
- Sicilian Defense: Smith-Morra Gambit Accepted, Morphy Defense — 1.e4 c5 2.d4 cxd4 3.c3 dxc3 4.Nxc3 Nc6 5.Nf3 e6 6.Bc4 Bc5
- Sicilian Defense: Smith-Morra Gambit Accepted, Morphy Defense Deferred — 1.e4 c5 2.d4 cxd4 3.c3 dxc3 4.Nxc3 Nc6 5.Nf3 e6 6.Bc4 a6 7.O-O b5 8.Bb3 Bc5
- Sicilian Defense: Smith-Morra Gambit Accepted, Paulsen Formation — 1.e4 c5 2.d4 cxd4 3.c3 dxc3 4.Nxc3 Nc6 5.Nf3 e6 6.Bc4 a6
- Sicilian Defense: Smith-Morra Gambit Accepted, Pin Defense — 1.e4 c5 2.d4 cxd4 3.c3 dxc3 4.Nxc3 Nc6 5.Nf3 e6 6.Bc4 Bb4
- Sicilian Defense: Smith-Morra Gambit Accepted, Scheveningen Formation — 1.e4 c5 2.d4 cxd4 3.c3 dxc3 4.Nxc3 Nc6 5.Nf3 d6 6.Bc4 e6
- Sicilian Defense: Smith-Morra Gambit Accepted, Siberian Variation — 1.e4 c5 2.d4 cxd4 3.c3 dxc3 4.Nxc3 Nc6 5.Nf3 e6 6.Bc4 Qc7
- Sicilian Defense: Smith-Morra Gambit Accepted, Siberian Variation, Siberian Trap — 1.e4 c5 2.d4 cxd4 3.c3 dxc3 4.Nxc3 Nc6 5.Nf3 e6 6.Bc4 Qc7 7.Qe2 Nf6 8.O-O Ng4
- Sicilian Defense: Smith-Morra Gambit Accepted, Sozin Formation — 1.e4 c5 2.d4 cxd4 3.c3 dxc3 4.Nxc3 Nc6 5.Bc4 e6 6.Nf3 d6 7.O-O a6 8.Qe2 b5
- Sicilian Defense: Smith-Morra Gambit Accepted, Taimanov Formation — 1.e4 c5 2.d4 cxd4 3.c3 dxc3 4.Nxc3 e6 5.Bc4 a6 6.Nf3 Ne7
- Sicilian Defense: Smith-Morra Gambit Declined, Alapin Formation — 1.e4 c5 2.d4 cxd4 3.c3 Nf6
- Sicilian Defense: Smith-Morra Gambit Declined, Center Formation — 1.e4 c5 2.d4 cxd4 3.c3 e5
- Sicilian Defense: Smith-Morra Gambit Declined, Dubois Variation — 1.e4 c5 2.d4 cxd4 3.c3 d3 4.c4
- Sicilian Defense: Smith-Morra Gambit Declined, Push Variation — 1.e4 c5 2.d4 cxd4 3.c3 d3
- Sicilian Defense: Smith-Morra Gambit Declined, Scandinavian Formation — 1.e4 c5 2.d4 cxd4 3.c3 d5
- Sicilian Defense: Smith-Morra Gambit Declined, Wing Formation — 1.e4 c5 2.d4 cxd4 3.c3 Qa5