WRHW
      +---------
TXLTG | HRPZLZXZ
       -QUWMT
        =====
         MJPGZ
        -TXLTG
         =====
         UHRQYX
        -UQYGTX
         ======
           QLHNZ
          -QUWMT
           =====
            YPYR

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