Marseille Chess is one of the different variants of chess in which each player moves twice per turn. His rules were first published in a local newspaper in Marseille at Le Soleil in 1925 and that's where his name comes from. This variant of chess was very popular at the end of the 1930s, played by great masters of the time such as Alekhine, Réti, Znosko-Borovsky. Rules
A player may move a piece twice or move two different pieces in turn. Castling is considered as a single movement.
When a player checks in on his first move, he loses the possibility of the second move of that turn. If a player is in check he must leave him in the first movement of his turn, if it is not possible to leave the check in the first movement then he can do it in the second.
The step capture can be made even if the opponent moved the corresponding pawn in the first movement of his previous turn. However, the capture in step must be done in the first movement of the turn. When two pawns can be captured in step after the opponent moves, both can be performed in the two movements of the turn.
To avoid too much advantage for White, a balanced version of the game is usually played. In the balanced version, White only makes one movement in the first turn. The movements are made in the following order: white, black, black, white, white, black, black, ... This rule was introduced in 1963 by Robert Bruce and since then had a great acceptance
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