????????
      +---------
WNYWU | LNYYNQEN
       -WNYWU
        =====
        WHHFPQ
       - PNGPP
        ======
          ENPFE
         -FGEFJ
          =====
           JYPNN
          -JHQJF
           =====
           ?????

base: 13
letters: EFGHJLNPQTUWY
difficulty: intermediate
missing: T