UZWT
      +---------
UPGPL | RGGWGLQZ
       -ZGYGU
        =====
        MJHTLL
       - XNGHP
        ======
         MTNZQQ
        -MQLRYW
         ======
          UWTZUZ
         -UWXMGY
          ======
            MHRX

base: 16
letters: GHJLMNPQRTUVWXYZ
difficulty: medium
missing: V