MWPN
      +---------
MNVMX | GNZHUHYN
       -PXWZG
        =====
        TPVYNH
       -TZHTTW
        ======
          HNWGY
         -LQVYU
          =====
          TWRRRN
         -TJJLXR
          ======
           TXHJH

base: 16
letters: GHJLMNPQRTUVWXYZ
difficulty: challenging
hints: H << U