Starting position #309
Back-rank setup: NQBBRKRN
SP-309 · BastionScout — Off-centre king plus a rim knight (a/h): 168 positions carry this shape.
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.
The bishops stand on c1 and d1; their long diagonals reach h6 and h5 once the d- and e-pawns step aside.
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 362.
The engine's main line opens with e4, putting a pawn straight into the centre.
Every sentence here is computed from the setup itself and can be checked on the board.
Balance
MBI 86 Morozov Balance Index: 86 of 100 — class A — most balanced.
- Engine evaluation of the starting position: +15 centipawns for White (depth 46, 400 000 000 nodes).
- Rank 142 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 (70 half-moves): +29 → +36 → +19 → 0
- Deeper check (1 200 000 000 nodes, depth 53): +24 cp, +9 cp against the base run — verified
Position facts
- Mirror twin: position #362
- The king starts on f, the rooks on e and g
- King and rook are neighbours — castling from adjacent squares feels unusual
- This position does not come up as the daily position in the next four years
Puzzles from this position
- Attack on the uncastled king: knight to h7 (g5) — Chess960 specifics · 620
- Attack on the uncastled king: pawn to h5 (g4·13) — Chess960 specifics · 780
- Attack on the uncastled king: rook to e8 (e1·7) — Chess960 specifics · 920
- Attack on the uncastled king: king to g1 (f1·3) — Chess960 specifics · 970
- Mate in 2: rook to e8 (d8) — Chess960 specifics · 1090
- Mate in 2: queen to f5 (h7) — Chess960 specifics · 1220
- Castling-960 to the rescue on g8 (f8) — Castling-960 · 1340
- Winning blow: rook to f8 (e8·3) — Chess960 specifics · 1510
- Winning blow: rook to h6 (d6·2) — Chess960 specifics · 1650
- Mate in 3: queen to h7 (h5·4) — Chess960 specifics · 2210
This position appears in course day 6
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Commentary
Both knights start in a corner, a1 and h1, each with a single move: b3 and g3. Short castling swaps the king on f1 with the rook on g1, and both sides castle that way in the engine's line: e4 e5 O-O Nb6 Ng3 O-O. The bishops stand side by side on c1 and d1, the queen on b1. On the second rank, h2 is the only one starting without a defender. The engine takes the centre first with e4 and keeps the edge small, +15 centipawns.
Written from the measured facts above and checked against the board before publishing. All 960 positions have one.