Irregular King’s Defences
MICOS Opening Group B00.IK – Irregular King’s Defences begins with 1.e4 followed by Black responses such as …a5, …a6, …b6, …f5, …f6, …g5, …h5, …h6, …Na6 or …Nh6. These defences create early asymmetry and move away from conventional opening patterns, often leading to unfamiliar positions where adaptability and strategic creativity become important. They offer Black different ways to challenge White’s opening play without immediately entering the more established King’s Pawn defence systems. Use the searchable table below to find openings by opening name, chess notation or MICOS code and train individual openings interactively with MICOS CAP.
Search by Opening Name, Chess Notation or MICOS Code. MICOS classifies each opening by its exact move order.
| Opening Name | Chess Notation | MICOS Code | MICOS CAP |
|---|---|---|---|
| King's Pawn Opening | 1.e4 | B00.001.IK | |
| Ware Defence | 1.e4 a5 | B00.002.IK | Explore ▶ |
| Ware Defence: Snaglepuss Defence | 1.e4 a5 2.d4 Nc6 | B00.003.IK | Explore ▶ |
| St. George Defence | 1.e4 a6 | B00.004.IK | Explore ▶ |
| St. George Defence: San Jorge Defence - Fianchetto | 1.e4 a6 2.d4 b5 3.Nf3 Bb7 4.Bd3 d6 5.O-O g6 6.c3 Bg7 | B00.005.IK | Explore ▶ |
| St. George Defence: Polish Defence | 1.e4 a6 2.d4 b5 3.Nf3 Bb7 4.Bd3 e6 | B00.006.IK | Explore ▶ |
| St. George Defence: Zilbermints Gambit | 1.e4 a6 2.d4 e5 | B00.007.IK | Explore ▶ |
| St. George Defence: New St. George - Three Pawn Attack | 1.e4 a6 2.d4 e6 3.c4 | B00.008.IK | Explore ▶ |
| St. George Defence: Woodchuck Defence | 1.e4 a6 2.d4 Nc6 | B00.009.IK | Explore ▶ |
| Owen's Defence | 1.e4 b6 | B00.010.IK | Explore ▶ |
| Owen's Defence: Guatemala Defence | 1.e4 b6 2.d4 Ba6 | B00.011.IK | Explore ▶ |
| Owen's Defence: Matovinsky Gambit | 1.e4 b6 2.d4 Bb7 3.Bd3 f5 | B00.012.IK | Explore ▶ |
| Owen's Defence: Matovinsky Gambit: 5…g6 | 1.e4 b6 2.d4 Bb7 3.Bd3 f5 4.exf5 Bxg2 5.Qh5+ g6 | B00.013.IK | Explore ▶ |
| Owen's Defence: Naselwaus Gambit | 1.e4 b6 2.d4 Bb7 3.Bg5 | B00.014.IK | Explore ▶ |
| Owen's Defence: Wind Gambit | 1.e4 b6 2.d4 Bb7 3.f3 e5 | B00.015.IK | Explore ▶ |
| Owen's Defence: Smith Gambit | 1.e4 b6 2.d4 Bb7 3.Nf3 | B00.016.IK | Explore ▶ |
| Owen's Defence: Hekili-Loa Gambit | 1.e4 b6 2.d4 c5 3.dxc5 Nc6 | B00.017.IK | Explore ▶ |
| Duras Gambit | 1.e4 f5 | B00.018.IK | Explore ▶ |
| Barnes Defence | 1.e4 f6 | B00.019.IK | Explore ▶ |
| Barnes Defence: Unicorn Defence | 1.e4 f6 2.d4 b6 3.c4 Bb7 | B00.020.IK | Explore ▶ |
| Fried Fox Defence | 1.e4 f6 2.d4 Kf7 | B00.021.IK | Explore ▶ |
| Borg Defence | 1.e4 g5 | B00.022.IK | Explore ▶ |
| Borg Defence: Borg Gambit | 1.e4 g5 2.d4 Bg7 | B00.023.IK | Explore ▶ |
| Borg Defence: Zilbermints Gambit | 1.e4 g5 2.d4 e5 | B00.024.IK | Explore ▶ |
| Borg Defence: Langhorst Gambit | 1.e4 g5 2.d4 e6 3.c3 c5 4.dxc5 b6 | B00.025.IK | Explore ▶ |
| Borg Defence: Troon Gambit | 1.e4 g5 2.d4 h6 3.h4 g4 | B00.026.IK | Explore ▶ |
| Goldsmith Defence | 1.e4 h5 | B00.027.IK | Explore ▶ |
| Goldsmith Defence: Picklepuss Defence | 1.e4 h5 2.d4 Nf6 | B00.028.IK | Explore ▶ |
| Carr Defence | 1.e4 h6 | B00.029.IK | Explore ▶ |
| Carr Defence: Zilbermints Gambit | 1.e4 h6 2.d4 e5 | B00.030.IK | Explore ▶ |
| Lemming Defence | 1.e4 Na6 | B00.031.IK | Explore ▶ |
| Hippopotamus Defence | 1.e4 Nh6 | B00.032.IK | Explore ▶ |
| Hippopotamus Defence: 3…f6 | 1.e4 Nh6 2.d4 g6 3.c4 f6 | B00.033.IK | Explore ▶ |
| Sub Groups | Chess Notation | MICOS CAP |
|---|---|---|
| Irregular King's Defences (B00.IK) | ||
| 25. St. George Defence | 1.e4 a6 | B00.004.IK 🖥️ |
| 26. Owen's Defence | 1.e4 b6 | B00.010.IK 🖥️ |
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