You don’t capture kings in chess, and I don’t think that changes in this variant (at least the article doesn’t suggest that). If you attack the square with the king on it, the king is in check. If there’s no legal move that puts the king out of check, that’s checkmate.
Perhaps interestingly, you can create a discovered check with two pieces on the same square, say two rooks. Like a double check in regular chess, you can’t remove the check by capturing, because you would only capture one of the rooks.
> Perhaps interestingly, you can create a discovered check with two pieces on the same square, say two rooks. Like a double check in regular chess, you can’t remove the check by capturing, because you would only capture one of the rooks.
That wouldn't work. The king would have been in check because of the first rook already, so either the king had to move away, the first rook would have been captured on the previous move, something would have been placed between the king and the rook, or it would have been checkmate.
Unless of course the two rooks would have been in place but you create the check by removing an obstacle, that would work.
