????????
      +---------
NXTXW | TCWTQTJN
       -NXTXW
        =====
        CJXGPT
       -CYQNYX
        ======
         CYJXCJ
        -CYQNYX
         ======
           TGRWN
          -NXTXW
           =====
           ?????

base: 12
letters: CGJLNPQRTWXY
difficulty: medium
missing: L