ecocodes
Volume C · Open games and the French Defense‹ C22C24 ›
a1b2c3d4e5f6g7h8
Reference position · Black to move

C23 Bishop’s Opening

C23 holds 24 named lines, all under the name Bishop’s Opening. It leaves C20 (King’s Pawn Game) with 2.Bc4. Material is no longer level at the end of eight of its lines; the widest gap, four pawns in Black’s favour, comes in Bishop’s Opening: Four Pawns Gambit. Of all other reference positions, the board of C24 (Berlin Defense) comes closest, two squares apart.

Score sheet
#WhiteBlack
1e4e5
2Bc4

The move that completes C23

The reference line of C24 plays all of these moves and continues beyond them; C23 is the position reached at 2.Bc4.

  1. 2.Bc4 The bishop leaves f1 for c4.

Lines filed under C23

All 24 share their first three plies, the whole reference line and then split five ways at Black’s move 2.

NameAfter the shared startPliesAt the end
Bishop’s Opening(the shared start itself)3
Bishop’s Opening: Boi Variation2...Bc54
Bishop’s Opening: Calabrese Countergambit2...f54
Bishop’s Opening: Khan Gambit2...d54
Bishop’s Opening: Philidor Counterattack2...c64
Bishop’s Opening: Calabrese Countergambit, Jaenisch Variation2...f5 3.d35
Bishop’s Opening: Lewis Gambit2...Bc5 3.d45
Bishop’s Opening: Lopez Variation2...Bc5 3.Qe25
Bishop’s Opening: McDonnell Gambit2...Bc5 3.b45
Bishop’s Opening: Philidor Variation2...Bc5 3.c35
Bishop’s Opening: Stein Gambit2...Bc5 3.f45
Bishop’s Opening: Anderssen Gambit2...b5 3.Bxb5 c66White +1
Bishop’s Opening: Lewis Countergambit2...Bc5 3.c3 d56
Bishop’s Opening: Thorold Gambit2...b5 3.Bxb5 f56White +1
Bishop’s Opening: del Rio Variation2...Bc5 3.c3 Qg56
Bishop’s Opening: Lopez Variation, Lopez Gambit2...Bc5 3.Qe2 Nf6 4.f47
Bishop’s Opening: McDonnell Gambit, La Bourdonnais-Denker Gambit2...Bc5 3.b4 Bxb4 4.c37Black +1
Bishop’s Opening: McDonnell Gambit, McDonnell Double Gambit2...Bc5 3.b4 Bxb4 4.f47Black +1
Bishop’s Opening: Lewis Countergambit2...Bc5 3.c3 d5 4.Bxd5 Nf68White +1
Bishop’s Opening: Lewis Countergambit, Walker Variation2...Bc5 3.c3 d5 4.Bxd5 Nf6 5.d49White +1
Bishop’s Opening: Lopez Gambit2...Bc5 3.Qe2 Nc6 4.c3 Nf6 5.f49
Bishop’s Opening: Pratt Variation2...Bc5 3.c3 Nf6 4.d4 exd4 5.e5 d5 6.exf6 dxc4 7.Qh5 O-O14Black +1, Black castled
Bishop’s Opening: Lisitsyn Variation2...c6 3.d4 d5 4.exd5 cxd5 5.Bb5+ Bd7 6.Bxd7+ Nxd7 7.dxe5 Nxe5 8.Ne215
Bishop’s Opening: Four Pawns Gambit2...Bc5 3.b4 Bxb4 4.f4 exf4 5.Nf3 Be7 6.d4 Bh4+ 7.g3 fxg3 8.O-O gxh2+ 9.Kh117Black +4, White castled

The road to C23

  1. 1.e4B00 King’s Pawn Game
  2. 1...e5C20 King’s Pawn Game
  3. 2.Bc4C23

The position after 2.Bc4

White has brought out the bishop on c4; Black has not yet moved a knight or bishop. Black is to move and has 29 legal moves.

WhiteBlackMaterial (pawn units)3939Minor pieces developed10Moves spent on pawns11Pawns on d4, e4, d5, e511Squares attacked in the other half75not castlednot castled

Codes that branch off from C23

The reference lines of one other code leave C23 from the position after 2.Bc4, each with its own moves.

CodeMovesReference line
C242...Nf6Bishop’s Opening: Berlin Defense

Closest boards in other codes

CodeLineDiffers on
B00King’s Pawn Gamefour squares: f1, c4, e5, e7
C00French Defensefour squares: f1, c4, e5, e6
C25Vienna Gamefour squares: b1, f1, c3, c4
C27Vienna Game: Frankenstein-Dracula Variationfour squares: b1, c3, e4, g8
C30King’s Gambitfour squares: f1, f2, c4, f4
C40King’s Knight Openingfour squares: f1, g1, f3, c4
C50Italian Gamefour squares: g1, f3, c6, b8

Where lines continue from here

Fourteen named lines filed under other codes pass through the position after 2.Bc4. Besides the codes above, they belong to C26, C30, C43.

Volume C

  1. 00
  2. 01
  3. 02
  4. 03
  5. 04
  6. 05
  7. 06
  8. 07
  9. 08
  10. 09
  11. 10
  12. 11
  13. 12
  14. 13
  15. 14
  16. 15
  17. 16
  18. 17
  19. 18
  20. 19
  21. 20
  22. 21
  23. 22
  24. 23
  25. 24
  26. 25
  27. 26
  28. 27
  29. 28
  30. 29
  31. 30
  32. 31
  33. 32
  34. 33
  35. 34
  36. 35
  37. 36
  38. 37
  39. 38
  40. 39
  41. 40
  42. 41
  43. 42
  44. 43
  45. 44
  46. 45
  47. 46
  48. 47
  49. 48
  50. 49
  51. 50
  52. 51
  53. 52
  54. 53
  55. 54
  56. 55
  57. 56
  58. 57
  59. 58
  60. 59
  61. 60
  62. 61
  63. 62
  64. 63
  65. 64
  66. 65
  67. 66
  68. 67
  69. 68
  70. 69
  71. 70
  72. 71
  73. 72
  74. 73
  75. 74
  76. 75
  77. 76
  78. 77
  79. 78
  80. 79
  81. 80
  82. 81
  83. 82
  84. 83
  85. 84
  86. 85
  87. 86
  88. 87
  89. 88
  90. 89
  91. 90
  92. 91
  93. 92
  94. 93
  95. 94
  96. 95
  97. 96
  98. 97
  99. 98
  100. 99

Open this line in the finderAll Bishop’s Opening codes