(defun make-game ()
  (let ((game (make-hash-table :test #'equal)))
    (iter (for p in '(t nil))
      (setf (gethash p game) (make-hash-table :test #'equal))
      (iter (for location in '("deck" "hand"))
        (setf (gethash location (gethash p game)) nil)))
    game))
(defvar x (make-game))
(setf (gethash "deck" (gethash t x)) '(0 1 2 3 4 5 6 7 8 9 10))
(defmacro let-game ((game player) &body body)
  `(let* ((player (gethash ,player ,game))
          (opponent (gethash (not ,player) ,game)))
     (declare (ignorable player))
     (declare (ignorable opponent))
     (macrolet ((hand (p) `(gethash "hand" (gethash ,p ,,game)))
                (deck (p) `(gethash "deck" (gethash ,p ,,game))))
       ,@body)))

(let-game (x t) (print (deck t)))