Starting position #361
Back-rank setup: NRKBBRQN
SP-361 · BastionScout — A c- or f-file king with at least one knight out on the edge.
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 f1, the queen on g1.
The king already stands on c1, so castling long moves only the rook, from b1 to d1.
The bishops stand on d1 and e1; their long diagonals reach h5 and a5 once the e- and d-pawns step aside.
One second-rank pawn starts with no defender at all: a2.
The setup belongs to the BastionScout family; read right to left it becomes position 313.
The engine's main line opens with f4.
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 45, 400 000 000 nodes).
- Rank 138 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): +31 → +39 → +9 → 0
- Deeper check (1 200 000 000 nodes, depth 49): +24 cp, +9 cp against the base run — verified
Position facts
- Mirror twin: position #313
- The king starts on c, the rooks on b and f
- King and rook are neighbours — castling from adjacent squares feels unusual
- It becomes the daily position in 374 days
Puzzles from this position
- Attack on the uncastled king: pawn to f5 (e4·48) — Chess960 specifics · 780
- Winning blow: queen to f1 (h1·2) — Chess960 specifics · 1060
- Attack on the uncastled king: queen to d4 (d6) — Chess960 specifics · 1110
- Attack on the uncastled king: rook to f2 (f4) — Chess960 specifics · 1200
- Winning blow: rook to h3 (g3·4) — Chess960 specifics · 1250
- Winning blow: queen to e1 (g3·2) — Chess960 specifics · 1340
- Mate in 3: knight to e6 (d4) — Chess960 specifics · 1630
- Mate in 3: pawn to g6 (f5·2) — Chess960 specifics · 1630
- Mate in 3: rook to b8 (b6) — Chess960 specifics · 1860
- Winning blow: rook to e7 (e1·31) — Chess960 specifics · 2060
This position appears in course day 125
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Commentary
Both castlings are half-moves here: the king already stands on c1 for the long one, and the rook already occupies f1 for the short. Both knights start in a corner, a1 and h1, each with a single move: b3 and g3. The bishops stand side by side on d1 and e1, the queen on g1. Among the pawns, a2 begins without a defender. The engine keeps the edge small, +15 centipawns: f4 f5 a4 a5 Nb3 d6.
Written from the measured facts above and checked against the board before publishing. All 960 positions have one.