p.boxed
	| Move twice at every turn.

h3 Specifications

ul
	li Chessboard: standard.
	li Material: standard.
	li Non-capturing moves: standard.
	li Special moves: standard.
	li Captures: standard.
	li End of game: standard.

p.
	The only difference with orthodox chess is the double-move rule,
	but this affects the game a lot.

h3 Basics

p.
	At the very first move of the game, white make only one move - as usual.
	However, after that and for all the game each side must play twice at
	every turn. There are two exceptions:

ul
	li.
		If the first move gives check (maybe checkmate),
		then a second move isn't played.
	li.
		If no move is available after the first move, then it's stalemate
		and again, there is no second move.

p.
	About the PGN game notation: when a side plays two moves in a row,
	they are separated (in order) by a comma in the PGN.
	Example: 3.Na5,Bd3 e6,f4 (the two first are white moves,
	the two others are black moves).

figure.diagram-container
	.diagram
		| fen:r1bqkbnr/pppp1p1p/2n5/4p2p/4P3/5N2/PPPP1PPP/RNB1KB1R:
	figcaption After the moves 1.e4 e5,Nc6 2.Qh5,Nf3 g6,gxh5

h3 En-passant capture

p.
	Capturing en-passant is allowed under certain conditions.
	If the opponent moved a pawn allowing such a capture (once or twice),
	then (to take it) you must capture en-passant at the first move of your turn.
	After that, if (and only if) there is another en-passant capture available
	you can play it on the second move.

p.
	Note: if a pawn 2-squares jump was made and then a piece landed at the
	en-passant square at the second move, a pawn capture on this square
	takes only the piece.
	And, if a pawn advanced twice then en-passant capture
	on its first movement is impossible (the pawn is now "too far").

h3 More information

p
	| See for example the 
	a(href="https://www.chessvariants.com/multimove.dir/marseill.html")
		|	Marseillais Chess
	|  page on chessvariants.com.