????????
      +---------
UQCME | QMYFQNCM
       -UQCME
        =====
        FUUYUN
       -FRJREY
        ======
         EQXRCC
        -EEMUEU
         ======
          UCMXJM
         -MJENEF
          ======
          ??????

base: 11
letters: CEFJMNQRUXY
difficulty: hard
hints: M-F != M