????????
      +---------
WFNQQ | UUEUUQNY
       -WFNQQ
        =====
         TJMEQ
        -NMJEE
         =====
          EUGXN
         -MTTLG
          =====
           FXYTY
          -FUYJT
           =====
           ?????

base: 13
letters: EFGJLMNQTUWXY
difficulty: medium