????????
      ----------
RTFFU ) NUWFMFYX
       -PXFFY
        =====
         NWFUF
        -PXFFY
         =====
          YFRYY
         -PXFFY
          =====
          RWRYFX
         -RUWFRY
          ======
           ?????

base: 12
symbols: CFMNPQRTUWXY
missing: C Q
difficulty: medium
hints: C << Q