Starting position #23
Back-rank setup: NQBNRKRB
SP-23 · BastionScout — King shifted to c or f, with a knight committed to the corner from move one.
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 e1 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 h1: it has a single diagonal, which the g-pawn unlocks, running out to a8.
One second-rank pawn starts with no defender at all: h2.
The setup belongs to the BastionScout family; read right to left it becomes position 930.
The engine's main line opens with g3.
Every sentence here is computed from the setup itself and can be checked on the board.
Balance
MBI 91 Morozov Balance Index: 91 of 100 — class A — most balanced.
- Engine evaluation of the starting position: +13 centipawns for White (depth 48, 400 000 000 nodes).
- Rank 99 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 (31 half-moves): +18 → 0
- Deeper check (1 200 000 000 nodes, depth 50): +20 cp, +7 cp against the base run — verified
Position facts
- Mirror twin: position #930
- The king starts on f, the rooks on e and g
- King and rook are neighbours — castling from adjacent squares feels unusual
- It becomes the daily position in 613 days
Puzzles from this position
- Attack on the uncastled king: pawn to f4 (g3·11) — Chess960 specifics · 780
- Attack on the uncastled king: pawn to e5 (f4·19) — Chess960 specifics · 780
- Attack on the uncastled king: bishop to h6 (d2·4) — Chess960 specifics · 780
- Attack on the uncastled king: bishop to h6 (c1·13) — Chess960 specifics · 920
- Winning blow: king to e1 (f1·10) — Chess960 specifics · 970
- Attack on the uncastled king: bishop to h6 (c1·15) — Chess960 specifics · 1090
- Winning blow: queen to a5 (c7·2) — Chess960 specifics · 1250
- Mate in 2: queen to d8 (d7·5) — Chess960 specifics · 1320
- Mate in 2: queen to e6 (f5·4) — Chess960 specifics · 1440
- Attack on the uncastled king: bishop to h3 (g2·10) — Chess960 specifics · 1890
This position appears in course day 37
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Commentary
Short castling here swaps two pieces: the king on f1 and the rook on g1 change places. A knight begins in the corner on a1 with b3 as its only move, and a bishop holds the other corner on h1, its diagonal to a8 opened by the g-pawn. The queen stands on b1, the second bishop on c1. Among the pawns, h2 starts with no defender. The engine's line opens g3 g6, then both sides castle at once — O-O O-O — before d3 Bg7.
Written from the measured facts above and checked against the board before publishing. All 960 positions have one.