Unfettered Genius

Well, okay.  You asked for it.  See, the thing is, we already KNOW what “the best game in the history of man" is.  There are really only two candidates, Chess, and Go.  Since chess has been played more widely (and this is not for an asian audience, which is where Go is most popular) the answer is clearly Chess.  It even has wide historical recognition as the proper owner of this title!

So now the problem is simplified.  Implement chess using only the provided tools.  Of course, actually doing this is not so simple.  I am ONLY guaranteed to have the board and as many of the pieces as I need.  Fortunately, there is a conveniently shameless loophole:  The relative size of the board, and the pieces, is unspecified.

Therefore I assume that the board is large enough that I can create the following eerily familiar diagram, using the (arbitrarily many) X pieces placed on it:

XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
X   X   X   X   X   X   X   X   X
X   X   X   X   X   X   X   X   X
X   X   X   X   X   X   X   X   X
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
X   X   X   X   X   X   X   X   X
X   X   X   X   X   X   X   X   X
X   X   X   X   X   X   X   X   X
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
X   X   X   X   X   X   X   X   X
X   X   X   X   X   X   X   X   X
X   X   X   X   X   X   X   X   X
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
X   X   X   X   X   X   X   X   X
X   X   X   X   X   X   X   X   X
X   X   X   X   X   X   X   X   X
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
X   X   X   X   X   X   X   X   X
X   X   X   X   X   X   X   X   X
X   X   X   X   X   X   X   X   X
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
X   X   X   X   X   X   X   X   X
X   X   X   X   X   X   X   X   X
X   X   X   X   X   X   X   X   X
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
X   X   X   X   X   X   X   X   X
X   X   X   X   X   X   X   X   X
X   X   X   X   X   X   X   X   X
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
X   X   X   X   X   X   X   X   X
X   X   X   X   X   X   X   X   X
X   X   X   X   X   X   X   X   X
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX

This creates a perfectly serviceable, if crude, chessboard.  Now, representing the various pieces takes a bit more work.

*  Each different type of piece is represented by a tower of O pieces, with the type
    of piece determined by the height (in pieces) of the tower

*  Black pieces are unadorned.  White towers (pieces) replace the top O piece with an X.

*  Pieces, by size of the tower:

    Pawn:    1
    Bishop:  2
    Knight:  3
    Rook:    4
    Queen:   5
    King:    6

Pieces are placed in the middle of each open space in the customary way (I will spare you the poor ASCII art, we all know how to play chess).

The chosen representation has several advantages:  Towers of the same height are always the same piece (Black king is a stack of 6 O's, white 5 O's and an X).  But they can be easily distinguished white from black by looking (X or O at the top).  Pieces are easy to move since they are one tower, which can easily be picked up, moved, and set down all at once, usually with one hand.  If the pieces were several towers or otherwise not one stack, moving them would be a much more laborious process.

Captured pieces need to go somewhere; we have ONLY the board.  Captured pieces are returned to the nebulous hammerspace portal from whence they came; if this is not possible, by even more shamelessly exploiting the loophole, we can fit the "logical chessboard" into less than the whole area of the board, and use that as the piece graveyard.

So here we have a chessboard and chesspieces.  The rest, I leave to Wikipedia ("chess is a game of pirates versus ninjas, a type of LARP without much action") since actually reciting the rules of chess is both redundant and boring.