????????
      +---------
WTXNW | MXGTEEUJ
       -WTXNW
        =====
        TNENME
       -NEQMUE
        ======
         TFMNFU
        -NEQMUE
         ======
           YUUMJ
          -WTXNW
           =====
           ?????

base: 13
letters: EFGJMNQRTUWXY
difficulty: intermediate
hints: R << J
missing: R