Syzygy endgame tablebases

Black is losing with DTZ 106

Ra1+ Loss with DTZ 105

Rb3+ Loss with DTZ 9 Ra2 Loss with DTZ 1 Ra4 Loss with DTZ 1 Ra5 Loss with DTZ 1 Ra6 Loss with DTZ 1 Rc3 Loss with DTZ 1 Rd3 Loss with DTZ 1 Re3 Loss with DTZ 1 Rf3 Loss with DTZ 1 Rg3 Loss with DTZ 1 Rh3 Loss with DTZ 1

This is a blessed loss. Mate can be forced, but a draw can be achieved under the fifty-move rule.

KQRBBvKR.pgn lichess.org

Histogram: KQRBB winning vs. KR (log scale)

⋮

Longest KQRBBvKR phases

KQRBBvKR statistics (unique positions)

White wins:
426,138,383,400 (99.7%)

Frustrated white wins:
80,126 (0.0%)

Draws:
1,101,104,630 (0.3%)

Black wins:
185,351,830 (0.0%)

KQRBBvKR.json (?)