Starting position #91
Back-rank setup: NNRKBRQB
SP-91 · ThroneScout — A central king (d or e), but with a knight posted out on the a- or h-file.
Move the pieces right on the board — full Chess960 rules, castle by dropping the king on the rook.
Position features
The king starts on d1, the rooks on c1 and f1, the queen on g1.
Castling long simply swaps the two pieces: the king on d1 and the rook on c1 trade places.
A bishop starts in the corner on h1: it has a single diagonal, which the g-pawn unlocks, running out to a8.
The second rank carries 2 pawns with no defender at all: a2, b2.
The setup belongs to the ThroneScout family; read right to left it becomes position 865.
The engine's main line opens with g4.
Every sentence here is computed from the setup itself and can be checked on the board.
Balance
MBI 26 Morozov Balance Index: 26 of 100 — class C — noticeable edge.
- Engine evaluation of the starting position: +34 centipawns for White (depth 45, 400 000 000 nodes).
- Rank 717 of 960 by balance — 1 is the most balanced start.
- Balance band M — moderate edge · dynamics along the play-out: stable
- Evaluation along the engine's main line (60 half-moves): +32 → +37 → +24 → +6
Position facts
- Mirror twin: position #865
- The king starts on d, the rooks on c and f
- King and rook are neighbours — castling from adjacent squares feels unusual
- It becomes the daily position in 164 days
Puzzles from this position
- Attack on the uncastled king: knight to b7 (a5·4) — Chess960 specifics · 620
- Attack on the uncastled king: rook to g1 (f1·2) — Chess960 specifics · 780
- Winning blow: bishop to h6 (d2·2) — Chess960 specifics · 920
- Winning blow: king to g2 (h2) — Chess960 specifics · 1110
- Winning blow: rook to a7 (h7) — Chess960 specifics · 1200
- Winning blow: queen to a6 (a8·2) — Chess960 specifics · 1290
- Winning blow: knight to c6 (a5·10) — Chess960 specifics · 1340
- Mate in 2: queen to g6 (d3·7) — Chess960 specifics · 1450
- Mate in 2: rook to f8 (f5·2) — Chess960 specifics · 1670
- Chess960 tactic on d3 (d1·2) — Chess960 specifics · 2400
This position appears in course day 7
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Commentary
Two castling quirks meet: the long one swaps the king on d1 with the rook on c1, and the short one moves the king alone, because the rook already occupies f1. A knight is in the corner on a1 with b3 as its only move, a bishop in the corner on h1 with one diagonal to a8. The queen stands on g1, the second bishop on e1. The pawns on a2 and b2 have no defender at all, and e2 has only the king. The published line opens g4 Nc6, then Nb3 f5 gxf5 g6 — the g-pawn takes on the fifth half-move.
Written from the measured facts above and checked against the board before publishing. All 960 positions have one.