????????
      +---------
QWUGY | TJUGTUHT
       -QWUGY
        =====
         HJJQU
        -QWUGY
         =====
         YTGMYH
        -YUTXJT
         ======
          UTWYYT
         -UYUWQW
          ======
          ??????

base: 12
letters: CGHJMNQTUWXY
missing: C N
difficulty: intermediate
hints: C << G