Syzygy endgame tablebases

Black is losing with DTZ 121

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

KRRRvKQQ.pgn lichess.org

Histogram: KRRR winning vs. KQQ (log scale)

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Longest KRRRvKQQ phases

KRRRvKQQ statistics (unique positions)

White wins:
85,645,647,498 (25.6%)
Frustrated white wins:
1,218,180 (0.0%)
Draws:
81,878,027,868 (24.4%)
Black wins:
167,494,625,502 (50.0%)
KRRRvKQQ.json (?)