PPYM
      +---------
PVLVP | PNRYTQGY
       -PVLVP
        =====
         LHQHQ
        -PVLVP
         =====
         PXZXVG
        -PPMUUY
         ======
          PZGQQY
         -PGWXTM
          ======
            NXWU

base: 16
letters: GHJLMNPQRTUVWXYZ
difficulty: intermediate
missing: J