B06 Modern Defense
Also filed here: Pterodactyl Defense, Rat Defense.
B06 holds 45 named lines from three openings, most of them (26) under Modern Defense. It leaves B00 (King’s Pawn Game) with 1...g6. Material is no longer level at the end of eight of its lines; the widest gap, one pawn in Black’s favour, comes in Modern Defense: Bishop Attack, Monkey’s Bum. With 45 named lines it is the third-largest code of the 100 codes in volume B.
| # | White | Black |
|---|---|---|
| 1 | e4 | g6 |
Moves only B06 plays
Same as B00 up to 1.e4, then:
- 1...g6 The g-pawn advances to g6, covering f5 and h5, opening a line for the bishop on f8.
Lines filed under B06
They begin with two different first moves.
| Name | After the shared start | Plies | At the end |
|---|---|---|---|
| Modern Defense | 1.e4 g6 | 2 | |
| Modern Defense | 1.e4 g6 2.d4 Bg7 | 4 | |
| Modern Defense: Fianchetto Gambit | 1.e4 g6 2.d4 f5 | 4 | |
| Modern Defense: Norwegian Defense | 1.e4 g6 2.d4 Nf6 | 4 | |
| Modern Defense: Bishop Attack | 1.e4 g6 2.d4 Bg7 3.Bc4 | 5 | |
| Modern Defense: Standard Line | 1.e4 g6 2.d4 Bg7 3.Nc3 | 5 | |
| Modern Defense: Three Pawns Attack | 1.e4 g6 2.d4 Bg7 3.f4 | 5 | |
| Modern Defense: Westermann Gambit | 1.e4 g6 2.d4 Bg7 3.Bd2 | 5 | |
| Modern Defense: Wind Gambit | 1.e4 g6 2.d4 Bg7 3.Bd3 | 5 | |
| Modern Defense: Bishop Attack, Bücker Gambit | 1.e4 g6 2.d4 Bg7 3.Bc4 b5 | 6 | |
| Modern Defense: Lizard Defense, Mittenberger Gambit | 1.e4 g6 2.d4 Bg7 3.Nc3 d5 | 6 | |
| Modern Defense: Modern Pterodactyl | 1.e4 g6 2.d4 Bg7 3.Nc3 c5 | 6 | |
| Modern Defense: Mongredien Defense, with Nc3 | 1.e4 g6 2.d4 Bg7 3.Nc3 b6 | 6 | |
| Modern Defense: Mongredien Defense, with Nf3 | 1.e4 g6 2.d4 Bg7 3.Nf3 b6 | 6 | |
| Modern Defense: Standard Defense | 1.e4 g6 2.d4 Bg7 3.Nc3 d6 | 6 | |
| Rat Defense: Accelerated Gurgenidze | 1.e4 g6 2.d4 d6 3.Nc3 c6 | 6 | |
| Modern Defense: Pseudo-Austrian Attack | 1.e4 g6 2.d4 Bg7 3.Nc3 d6 4.f4 | 7 | |
| Modern Defense: Two Knights Variation | 1.e4 g6 2.d4 Bg7 3.Nc3 d6 4.Nf3 | 7 | |
| Pterodactyl Defense: Eastern, Anhanguera | 1.e4 g6 2.d4 Bg7 3.Nc3 c5 4.Be3 | 7 | |
| Pterodactyl Defense: Eastern, Benoni | 1.d4 g6 2.e4 Bg7 3.Nc3 c5 4.d5 | 7 | |
| Modern Defense: Bishop Attack, Monkey’s Bum | 1.e4 g6 2.Bc4 Bg7 3.Qf3 e6 4.d4 Bxd4 | 8 | Black +1 |
| Modern Defense: Norwegian Defense, Norwegian Gambit | 1.e4 g6 2.d4 Nf6 3.e5 Nh5 4.Be2 d6 | 8 | |
| Modern Defense: Two Knights Variation, Suttles Variation | 1.e4 g6 2.d4 Bg7 3.Nc3 c6 4.Nf3 d6 | 8 | |
| Pterodactyl Defense: Austrian, Austriadactylus Western | 1.e4 g6 2.d4 Bg7 3.f4 c5 4.Nf3 Qa5+ | 8 | check |
| Pterodactyl Defense: Austrian, Grand Prix Pterodactyl | 1.e4 g6 2.Nc3 Bg7 3.f4 c5 4.Nf3 Qa5 | 8 | |
| Pterodactyl Defense: Austrian, Pteranodon | 1.e4 g6 2.d4 Bg7 3.f4 c5 4.c3 Qa5 | 8 | |
| Pterodactyl Defense: Eastern, Benoni Pterodactyl | 1.d4 g6 2.Nc3 Bg7 3.e4 c5 4.d5 Qa5 | 8 | |
| Pterodactyl Defense: Eastern, Rhamphorhynchus | 1.e4 g6 2.d4 Bg7 3.Nc3 c5 4.dxc5 Qa5 | 8 | White +1 |
| Pterodactyl Defense: Fianchetto, King Pterodactyl | 1.e4 g6 2.d4 Bg7 3.g3 c5 4.Nf3 Qa5+ | 8 | check |
| Pterodactyl Defense: Fianchetto, Rhamphorhynchus | 1.e4 g6 2.d4 Bg7 3.g3 c5 4.dxc5 Qa5+ | 8 | White +1, check |
| Pterodactyl Defense: Western, Anhanguera | 1.e4 g6 2.d4 Bg7 3.Nf3 c5 4.Be3 Qa5+ | 8 | check |
| Modern Defense: Anti-Modern | 1.e4 g6 2.d4 Bg7 3.Nc3 c6 4.Bc4 d6 5.Qe2 | 9 | |
| Pterodactyl Defense: Sicilian, Siroccopteryx | 1.e4 g6 2.d4 Bg7 3.Nc3 c5 4.Nf3 Qa5 5.Bc4 | 9 | |
| Modern Defense: Dunworthy Variation | 1.e4 g6 2.d4 Bg7 3.c4 d5 4.exd5 c6 5.dxc6 Bxd4 | 10 | White +1 |
| Modern Defense: Gurgenidze Defense | 1.e4 g6 2.d4 Bg7 3.Nc3 c6 4.f4 d5 5.e5 h5 | 10 | |
| Modern Defense: Masur Gambit | 1.e4 g6 2.d4 Nh6 3.Nc3 f5 4.Bxh6 Bxh6 5.exf5 O-O | 10 | White +1, Black castled |
| Modern Defense: Semi-Averbakh Variation, Pterodactyl Variation Declined | 1.e4 g6 2.d4 Bg7 3.c4 c5 4.Nf3 d6 5.Be2 Qa5+ | 10 | check |
| Pterodactyl Defense: Central, Anhanguera | 1.e4 g6 2.d4 Bg7 3.c4 c5 4.Nc3 d6 5.Be3 Qa5 | 10 | |
| Pterodactyl Defense: Central, Benoni Quetzalcoatlus | 1.e4 g6 2.d4 Bg7 3.c4 c5 4.d5 d6 5.Nc3 Qa5 | 10 | |
| Pterodactyl Defense: Central, Quetzalcoatlus Gambit | 1.e4 g6 2.d4 Bg7 3.c4 c5 4.Nc3 d6 5.dxc5 Qa5 | 10 | White +1 |
| Pterodactyl Defense: Eastern, Benoni Pteranodon | 1.e4 g6 2.d4 Bg7 3.Nc3 c5 4.d5 Bxc3+ 5.bxc3 Qa5 | 10 | |
| Pterodactyl Defense: Eastern, Pteranodon | 1.e4 g6 2.d4 Bg7 3.Nc3 c5 4.dxc5 Bxc3+ 5.bxc3 Qa5 | 10 | White +1 |
| Pterodactyl Defense: Sicilian, Quetzalcoatlus | 1.e4 g6 2.d4 Bg7 3.Nc3 c5 4.Nf3 Qa5 5.Be2 d6 | 10 | |
| Pterodactyl Defense: Western, Siroccopteryx | 1.e4 g6 2.Nf3 Bg7 3.d4 c5 4.Bc4 cxd4 5.Nxd4 Qa5+ | 10 | check |
| Modern Defense: Two Knights Variation, Suttles Variation, Tal Gambit | 1.e4 g6 2.d4 Bg7 3.Nc3 d6 4.Nf3 c6 5.Bg5 Qb6 6.Qd2 Qxb2 | 12 | Black +1 |
The road to B06
- 1.e4B00 King’s Pawn Game
- 1...g6B06
The position after 1...g6
White is to move and has 30 legal moves.
Closest boards in other codes
| Code | Line | Differs on |
|---|---|---|
| B01 | Scandinavian Defense | four squares: d5, g6, d7, g7 |
| B02 | Alekhine Defense | four squares: f6, g6, g7, g8 |
| B10 | Caro-Kann Defense | four squares: c6, g6, c7, g7 |
| B20 | Sicilian Defense | four squares: c5, g6, c7, g7 |
| C00 | French Defense | four squares: e6, g6, e7, g7 |
| C20 | King’s Pawn Game | four squares: e5, g6, e7, g7 |
| B34 | Sicilian Defense: Accelerated Dragon, Exchange Variation | five squares: g1, d2, c6, c7, b8 |
Where lines continue from here
One named line filed under other codes passes through the position after 1...g6. It belongs to B07.