ECO C40
40 named openings and variations are classified as C40. ECO (Encyclopaedia of Chess Openings) codes group openings from A00 to E99 by their opening moves.
- Elephant GambitC401. e4 e5 2. Nf3 d5
- Elephant Gambit: Maróczy GambitC401. e4 e5 2. Nf3 d5 3. exd5 Bd6
- Elephant Gambit: Paulsen CountergambitC401. e4 e5 2. Nf3 d5 3. exd5 e4
- Elephant Gambit: Wasp VariationC401. e4 e5 2. Nf3 d5 3. Nxe5 dxe4 4. Bc4 Qg5
- Gunderam DefenseC401. e4 e5 2. Nf3 Qe7
- King's Knight OpeningC401. e4 e5 2. Nf3
- King's Pawn Game: Busch-Gass GambitC401. e4 e5 2. Nf3 Bc5
- King's Pawn Game: Busch-Gass Gambit, Chiodini GambitC401. e4 e5 2. Nf3 Bc5 3. Nxe5 Nc6
- King's Pawn Game: Damiano DefenseC401. e4 e5 2. Nf3 f6
- King's Pawn Game: Damiano Defense, Damiano GambitC401. e4 e5 2. Nf3 f6 3. Nxe5 fxe5 4. Qh5+ g6 5. Qxe5+ Qe7 6. Qxh8
- King's Pawn Game: Damiano Defense, Damiano Gambit, Chigorin GambitC401. e4 e5 2. Nf3 f6 3. Nxe5 Qe7 4. Nf3 d5
- King's Pawn Game: Gunderam Defense, Gunderam GambitC401. e4 e5 2. Nf3 Qe7 3. Bc4 f5
- King's Pawn Game: Gunderam GambitC401. e4 e5 2. Nf3 c6
- King's Pawn Game: La Bourdonnais GambitC401. e4 e5 2. Nf3 Qf6 3. Bc4 Qg6 4. O-O
- King's Pawn Game: McConnell DefenseC401. e4 e5 2. Nf3 Qf6
- Latvian GambitC401. e4 e5 2. Nf3 f5
- Latvian Gambit AcceptedC401. e4 e5 2. Nf3 f5 3. exf5
- Latvian Gambit Accepted: Bilguer VariationC401. e4 e5 2. Nf3 f5 3. Nxe5 Qf6 4. d4 d6 5. Nc4
- Latvian Gambit Accepted: Bronstein AttackC401. e4 e5 2. Nf3 f5 3. Nxe5 Qf6 4. d4 d6 5. Nc4 fxe4 6. Be2
- Latvian Gambit Accepted: Bronstein GambitC401. e4 e5 2. Nf3 f5 3. Nxe5 Qf6 4. d4 d6 5. Nc4 fxe4 6. Qh5+ g6 7. Qe2
- Latvian Gambit Accepted: Foltys VariationC401. e4 e5 2. Nf3 f5 3. Nxe5 Qf6 4. Nc4 fxe4 5. d3
- Latvian Gambit Accepted: Foltys-Leonhardt VariationC401. e4 e5 2. Nf3 f5 3. Nxe5 Qf6 4. Nc4
- Latvian Gambit Accepted: Leonhardt VariationC401. e4 e5 2. Nf3 f5 3. Nxe5 Qf6 4. Nc4 fxe4 5. Nc3
- Latvian Gambit Accepted: Main LineC401. e4 e5 2. Nf3 f5 3. Nxe5 Qf6 4. d4
- Latvian Gambit Accepted: Nimzowitsch AttackC401. e4 e5 2. Nf3 f5 3. Nxe5 Qf6 4. d4 d6 5. Nc4 fxe4 6. Ne3
- Latvian Gambit: Behting VariationC401. e4 e5 2. Nf3 f5 3. Bc4 fxe4 4. Nxe5 Qg5 5. Nf7 Qxg2 6. Rf1 d5 7. Nxh8 Nf6
- Latvian Gambit: Corkscrew CountergambitC401. e4 e5 2. Nf3 f5 3. Bc4 fxe4 4. Nxe5 Nf6
- Latvian Gambit: Corkscrew GambitC401. e4 e5 2. Nf3 f5 3. Nxe5 Nf6 4. Bc4 fxe4 5. Nf7 Qe7 6. Nxh8 d5
- Latvian Gambit: Diepstraten CountergambitC401. e4 e5 2. Nf3 f5 3. c4
- Latvian Gambit: Fraser DefenseC401. e4 e5 2. Nf3 f5 3. Nxe5 Nc6
- Latvian Gambit: Greco VariationC401. e4 e5 2. Nf3 f5 3. Nxe5 Qe7
- Latvian Gambit: Lobster GambitC401. e4 e5 2. Nf3 f5 3. g4
- Latvian Gambit: Mason CountergambitC401. e4 e5 2. Nf3 f5 3. d4
- Latvian Gambit: Mayet AttackC401. e4 e5 2. Nf3 f5 3. Bc4
- Latvian Gambit: Mayet Attack, Morgado DefenseC401. e4 e5 2. Nf3 f5 3. Bc4 Nf6
- Latvian Gambit: Mayet Attack, Poisoned Pawn VariationC401. e4 e5 2. Nf3 f5 3. Bc4 fxe4 4. Nxe5 Qg5 5. d4 Qxg2
- Latvian Gambit: Mayet Attack, Polerio-Svedenborg VariationC401. e4 e5 2. Nf3 f5 3. Bc4 fxe4 4. Nxe5 d5
- Latvian Gambit: Mayet Attack, Strautins GambitC401. e4 e5 2. Nf3 f5 3. Bc4 b5
- Latvian Gambit: Mlotkowski VariationC401. e4 e5 2. Nf3 f5 3. Nc3
- Latvian Gambit: Senechaud GambitC401. e4 e5 2. Nf3 f5 3. b4