WTRL
      +---------
QFNPH | XLRHLRTU
       -QFNPH
        =====
        RMMQWR
       -RLGYUQ
        ======
         GLTHHT
        -GGUTQL
         ======
          NPGFMU
         -NUUGWF
          ======
           TQQLQ

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