I was thinking about some rules and I came up with a really nice question. Is it possible to castle with a pawn promoted to a rook?
If the rules are followed-neither the king or the new rook has moved and king doesn’t move out of or through check-to me it seems to be a legal move.
If it possbile, how would this castling look like? I suspect that the king would go to e3, and the new rook would go to e2, starting from the below diagram.
[FEN "8/4P3/8/8/8/8/8/4K3 w - - 0 1"] 1. e8=R