????????
      +---------
LXJQL | WRXFHUNP
       -WWHPP
        =====
         GMQMU
        -HNMFM
         =====
         LNLTTN
        -LLLQFF
         ======
          LYMYGP
         - UMFPG
          ======
          ??????

base: 15
letters: FGHJLMNPQRTUWXY
difficulty: intermediate