?????????
      +----------
JUJRN | MVVPWMLGY
       -UVMTZ
        =====
        JZZNWM
       - YTHLZ
        ======
          UTRML
         -UVMTZ
          =====
           WHQLG
          -WZYVZ
           =====
            WGGGY
           -WZYVZ
            =====
            ?????

base: 16
letters: GHJLMNPQRTUVWXYZ
difficulty: hard
missing: X