????????
      +---------
PWHHP | GURWFRHW
       -PWHHP
        =====
        LGULHR
       -LMFMPM
        ======
         HLFYPH
        -LRXGFR
         ======
          HXLXJW
         -HMQYXN
          ======
          ??????

base: 15
letters: FGHJLMNPQRTUWXY
difficulty: hard
missing: T