When there are multiple parallel time-lines, you have to input a move for each one before you can advance to the next turn. But to win, you have to mate just one of the opponent's kings. One player can have multiple kings on one board, because they can move through time and between time-lines.
I have no idea what high-level play will end up looking like, but the streamer from whom I learned the above [0] said that the most common way to win is to mate a king on a board in the past. Those already have their options of escaping an attack restricted by ordinary chess rules; it gets worse when you can make additional threats from the future.
I'd think the same way you know you won regular chess. You capture the opponent's king. Checkmate is just an acknowledgement that the current player has no way of avoiding their opponent from taking their king on the next move.
No, checkmate is the end state of the game, and the king cannot be captured. Any action by a player that would allow their king to be captured is an illegal move. When one player has no more legal moves, the game is over.
How do you reckon that? I mean, it makes sense on an intuitive level; however, since now we're not talking about Conor Petersen's 5D chess, but the vast space of possible multiverse time travel chess variants, it's not obvious how one could prove this to be impossible in a somewhat rigorous way. For example, what if time-lines end when a king is mated (or wioll fore-when haven been mote [0]), but you only lose when you can't make a valid move in any time-line?
You do , which is why it ends up being easier to attack kings in the past. Because you can't change the past, only create new timelines, attacking a king from any previous board state means that the attacking piece must be captured.
Yes, but it's not that easy. Pieces still make threats according to their movement rules, whether through time or space.
For example, if your king moves from its square and an enemy rook attacks its starting position (rooks can move any number of squares in any one direction), then it's mate unless you can take the rook. However, if in the intervening time, another piece lands on the same spot, then it will block subsequent rook checks through time on that square.
