NXWC
      +---------
GCWUG | JQQWMWCG
       -JMJPJ
        =====
         RTWXW
        -RMMTR
         =====
          QGNJC
         -QMRWQ
          =====
            PNWG

base: 12
letters: CGJMNPQRTUWX
difficulty: medium