Starting position #176
Back-rank setup: BBNRNKRQ
SP-176 · BastionGuard — A c- or f-file king and two knights on inner files (b–g).
Move the pieces right on the board — full Chess960 rules, castle by dropping the king on the rook.
Position features
The king starts on f1, the rooks on d1 and g1, the queen on h1.
Castling short simply swaps the two pieces: the king on f1 and the rook on g1 trade places.
A bishop starts in the corner on a1: it has a single diagonal, which the b-pawn unlocks, running out to h8.
The pawn on f2 is defended by the king alone — the classic soft spot of the standard setup.
The setup belongs to the BastionGuard family; read right to left it becomes position 783.
The engine's main line opens with g4.
Every sentence here is computed from the setup itself and can be checked on the board.
Balance
MBI 2 Morozov Balance Index: 2 of 100 — class D — largest edge.
- Engine evaluation of the starting position: +53 centipawns for White (depth 44, 400 000 000 nodes).
- Rank 945 of 960 by balance — 1 is the most balanced start.
- Balance band L — large edge · dynamics along the play-out: equalizing
- Evaluation along the engine's main line (60 half-moves): +48 → +33 → 0
Position facts
- Mirror twin: position #783
- The king starts on f, the rooks on d and g
- King and rook are neighbours — castling from adjacent squares feels unusual
- It becomes the daily position in 24 days
Puzzles from this position
- Attack on the uncastled king: queen to a8 (h1·2) — Chess960 specifics · 780
- Attack on the uncastled king: knight to e6 (c5·4) — Chess960 specifics · 780
- Attack on the uncastled king: queen to d7 (h3) — Chess960 specifics · 780
- Winning blow: bishop to e2 (d1) — Chess960 specifics · 970
- Winning blow: knight to b8 (a6·2) — Chess960 specifics · 1060
- Attack on the uncastled king: knight to f3 (e1·2) — Chess960 specifics · 1110
- Winning blow: rook to h3 (g3·3) — Chess960 specifics · 1200
- Mate in 2: rook to d7 (d2) — Chess960 specifics · 1450
- Mate in 2: knight to e5 (d3·3) — Chess960 specifics · 1630
- Mate in 3: queen to e8 (c8·6) — Chess960 specifics · 1990
This position appears in course day 18
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Commentary
Short castling swaps the king on f1 with the rook on g1, while long castling moves the king alone, because the rook already stands on d1. The queen begins in the corner on h1, a bishop in the other corner on a1 with a single diagonal to h8. Among the pawns, f2 is defended by the king alone. The second bishop works the light squares from b1, the knights hold c1 and e1. The recorded line opens g4 g6, then d4 c5 dxc5 d5.
Written from the measured facts above and checked against the board before publishing. All 960 positions have one.