Syzygy endgame tablebases
White to move
Black to move
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White is losing with DTZ 133
Ka1
Loss with DTZ 132
Kc1
Loss with DTZ 128
This is a blessed loss.
Mate can be forced, but a draw can be achieved under the fifty-move rule.
KRBBvKQ.pgn
lichess.org
Histogram: KRBB losing vs. KQ (log scale)
⋮
Longest KRBBvKQ phases
KRBB winning with DTZ 88
KRBB losing with DTZ 134 (frustrated)
KRBB losing with DTZ 51
KRBBvKQ statistics (unique positions)
White wins:
2,350,565,700 (30.3%)
Draws:
3,882,463,509 (50.0%)
Frustrated black wins:
125,049,432 (1.6%)
Black wins:
1,400,809,507 (18.1%)
KRBBvKQ.json
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