Starting position #754
Back-rank setup: BRKNNBRQ
SP-754 · BastionGuard — Both knights begin inside the board while the king stands on c or f; a position and its mirror twin share this family.
Move the pieces right on the board — full Chess960 rules, castle by dropping the king on the rook.
Position features
The king starts on c1, the rooks on b1 and g1, the queen on h1.
The king already stands on c1, so castling long moves only the rook, from b1 to d1.
A bishop starts in the corner on a1: it has a single diagonal, which the b-pawn unlocks, running out to h8.
One second-rank pawn starts with no defender at all: a2.
The setup belongs to the BastionGuard family; read right to left it becomes position 391.
The engine's main line opens with b3.
Every sentence here is computed from the setup itself and can be checked on the board.
Balance
MBI 78 Morozov Balance Index: 78 of 100 — class A — most balanced.
- Engine evaluation of the starting position: +18 centipawns for White (depth 42, 400 000 000 nodes).
- Rank 212 of 960 by balance — 1 is the most balanced start.
- Balance band S — slight edge · dynamics along the play-out: sharpening
- Evaluation along the engine's main line (50 half-moves): +30 → +47 → +33 → +26
Position facts
- Mirror twin: position #391
- The king starts on c, the rooks on b and g
- King and rook are neighbours — castling from adjacent squares feels unusual
- It becomes the daily position in 641 days
Puzzles from this position
- Attack on the uncastled king: pawn to c3 (d2) — Chess960 specifics · 780
- Winning blow: pawn to g5 (f4·3) — Chess960 specifics · 780
- Winning blow: bishop to c3 (b2·2) — Chess960 specifics · 780
- Attack on the uncastled king: rook to d1 (b1) — Chess960 specifics · 920
- Mate in 2: queen to a6 (c6) — Chess960 specifics · 1320
- Winning blow: queen to c8 (a6·2) — Chess960 specifics · 1390
- Winning blow: knight to d7 (f6·9) — Chess960 specifics · 1430
- Mate in 2: queen to b7 (b5·3) — Chess960 specifics · 1450
- Attack on the uncastled king: queen to a8 (a6·3) — Chess960 specifics · 1630
- Chess960 tactic on a7 (b7) — Chess960 specifics · 2350
This position appears in course day 47
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Commentary
The king already stands on c1, so long castling moves the rook alone from b1. A bishop is shut into the corner on a1 with a single diagonal to h8; the second bishop is on f1. Among the pawns, a2 has no defender, and d2 leans on the king alone. The queen begins in the far corner on h1, the knights side by side on d1 and e1. The main line of the run opens b3 b6, then f3 f6 e4 e5.
Written from the measured facts above and checked against the board before publishing. All 960 positions have one.