Syzygy endgame tablebases

Black is losing with DTZ 120

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

KQBBvKRR.pgn lichess.org

Histogram: KQBB winning vs. KRR (log scale)

Longest KQBBvKRR phases

KQBBvKRR statistics (unique positions)

White wins:
303,675,036,672 (74.9%)
Frustrated white wins:
24,694,212 (0.0%)
Draws:
57,839,649,134 (14.3%)
Black wins:
43,745,429,172 (10.8%)
KQBBvKRR.json (?)