Starting position #387
Back-rank setup: BQRNNKRB
SP-387 · BastionGuard — King shifted to c or f, knights kept clear of the edges — 168 positions in all.
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 c1 and g1, the queen on b1.
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 second rank carries 2 pawns with no defender at all: d2, h2.
The setup belongs to the BastionGuard family; read right to left it becomes position 755.
The engine's main line opens with b4.
Every sentence here is computed from the setup itself and can be checked on the board.
Balance
MBI 83 Morozov Balance Index: 83 of 100 — class A — most balanced.
- Engine evaluation of the starting position: +16 centipawns for White (depth 49, 400 000 000 nodes).
- Rank 167 of 960 by balance — 1 is the most balanced start.
- Balance band S — slight edge · dynamics along the play-out: stable
- Evaluation along the engine's main line (60 half-moves): +31 → +2 → 0
Position facts
- Mirror twin: position #755
- The king starts on f, the rooks on c and g
- King and rook are neighbours — castling from adjacent squares feels unusual
- It becomes the daily position in 31 days
Puzzles from this position
- Attack on the uncastled king: pawn to d5 (c4·7) — Chess960 specifics · 780
- Winning blow: pawn to e4 (e3) — Chess960 specifics · 970
- Attack on the uncastled king: knight to c5 (d3·9) — Chess960 specifics · 1060
- Winning blow: rook to d4 (d1·7) — Chess960 specifics · 1200
- Mate in 2: knight to f7 (e5) — Chess960 specifics · 1220
- Winning blow: bishop to d5 (f3·7) — Chess960 specifics · 1290
- Mate in 3: pawn to c4 — Chess960 specifics · 1630
- Mate in 3: queen to h8 (h6·2) — Chess960 specifics · 1760
- Winning blow: queen to g2 (b2) — Chess960 specifics · 2060
- Chess960 tactic on h7 (g7) — Chess960 specifics · 2400
This position appears in course day 61
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Commentary
Both corners hold a bishop, a1 towards h8 and h1 towards a8, each with a single diagonal — and in the engine's line the second one is taken: after b4 b5 Ne3 Ne6 g3 comes Bxh1. Short castling swaps the king on f1 with the rook on g1. Two pawns begin with no defender at all: d2 and h2, and e2 leans on the king alone. The queen is on b1, the knights on d1 and e1. The search ran to depth 49 and calls it +16 centipawns.
Written from the measured facts above and checked against the board before publishing. All 960 positions have one.