HNY
      +---------
PTNHQ | HUFEYPNY
       -YPQYFT
        ======
         NWFNWN
        -UPNENW
         ======
          YNUGUY
         -WPGFXH
          ======
           NXTGP

base: 13
letters: EFGHJNPQTUWXY
difficulty: intermediate
restrictions: no multiplication
missing: J