????????
      +---------
CRHNL | PCUPPURH
       -CRHNL
        =====
        QQJPNU
       - FUFFP
        ======
         RCHQCR
        -RJUPUR
         ======
          RFUUJH
         -RUQUHQ
          ======
          ??????

base: 11
letters: CFGHJLNPQRU
difficulty: intermediate
missing: G