Single Comment

I can't rate the game as written; it looks great, but I haven't played
it.

I just want to add that my personal group of Chess dorks got together for
some Bughouse only to have one member fail to show.  Left with three
players, we decided to try Besiege Chess as a three-player game instead:
white, black, and yellow (another color we happened to have on hand). 
White and yellow both had orthodox sets, while black retained it's double
set and three queens.  Each player got one move per round, going in the
order white, black, yellow.

The resulting game was amazing.  It was like a cross between Chess and
Diplomacy.  Black was initially savaged by the two-front war, but things
changed rapidly when white and yellow realized that whoever expended more
resources destroying black would likely lose to the other.  It became a
protracted and exciting battle, with players sometimes declining to take
opposing rooks or queens of one side because the position they were in
gave them an advantage over, or at least temporarily distracted, the
other.

There were double-checks, in which a piece from one army would check both
enemy kings at once.  There was an instance in which one king found
himself in check from both other players.  We conceived of scenarios in
which one player could inadvertently assist in the checkmate of another by
the third.

The first checkmated player had all his pieces removed from the board to
allow the others to finish.  Next time, however, we plan to have it so
that the player who captures another's king gets control of his remaining
pieces.  This will encourage more aggression and discourage turtling.

It was great fun.  Thanks to the author of Besiege Chess for giving us the
idea.