LZJV
      +---------
JLPJR | TYRRYNXT
       -TJVTY
        =====
         RMXGN
        -JLPJR
         =====
         ZJRHVX
        -ZGQXZJ
         ======
          NHVXQT
         -NYLRUM
          ======
           ZUPXL

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