Similarly, what if the queen becomes the king upon checkmate, if the queen is still on the board? (If not, checkmate of the king ends the game.) Inspired by various board games of Lord of the Rings in which Sam can become the ringbearer if something happens to Frodo.
variant idea: coregal chess

Similarly, what if the queen becomes the king upon checkmate, if the queen is still on the board? (If not, checkmate of the king ends the game.) Inspired by various board games of Lord of the Rings in which Sam can become the ringbearer if something happens to Frodo.
wdym if the queen becomes the king? if queen or king gets checkmated, anyone of them, player loses
coregal chess. the queen is subject to check and checkmate, just like the king. if the queen or the king is checkmated, the checkmating player wins. castling works both ways for the queen and the king(castling rules apply). pawns can promote to queen, but that queen will also be subject to check and checkmate. this means that scholar's mate does not work, and that queens cannot give a check from one square. i think this would be rlly interesting