Syzygy endgame tablebases

Black is losing with DTZ 132

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

KQQRvKQB.pgn lichess.org

Histogram: KQQR winning vs. KQB (log scale)

Longest KQQRvKQB phases

KQQRvKQB statistics (unique positions)

White wins:
307,069,153,812 (92.3%)
Frustrated white wins:
855,214 (0.0%)
Draws:
20,813,897,138 (6.3%)
Black wins:
4,752,451,692 (1.4%)
KQQRvKQB.json (?)