2 Rook and bishop can fusion to become a queen, if the queen disappeared.
5 If a side lacks a queen, then a special fusion move is allowed by "capturing"
6 a rook with a bishop (and conversely).
7 The result of the capture is a queen, hence the variant name.
9 figure.diagram-container
11 | fen:1R6/1pr2k2/p1p1p2p/3p3p/2nP3P/1NP3P1/PPK1P3/2R3B1:
13 | fen:1R6/1pr2k2/p1p1p2p/3p3p/2nP3P/1NP3P1/PPK1P3/6Q1:
14 figcaption Left: before Rxg1=Q. Right: after the move.
20 a(href="https://www.chessvariants.com/play/erf/CoronatC.html") mentioned here