Single Comment

I think the two consecutive moves given to the opponent may need to be
clarified a little more.  Can the player put the King in check with his
first move?  And if so, couldn't he just capture the King on his second? 
You might want to adopt the rule from Marseillais Chess that says that if
you put the King in check with your first move, you forfit the second
move.

And are there any other restricitons?  Can the same piece move for both of
the moves?  What if the two moves are both a two-space initial pawn move;
in that case is it possible to do an En Passant on either one of those
moves, or only the second one?  And what about the player placing his own
King in check with the first move and then moving it out of check with the
second?