That was my first question, but then I realized you’d need more than just one magnet per square, as it’s possible for a knight to capture something without an e

That was my first question, but then I realized you’d need more than just one magnet per square, as it’s possible for a knight to capture something without an exit path. Or you would need some path finding software. To figure out what pieces you’d need to move first, to be able to remove the captured piece. And I wonder what this board does when you promote a second queen?