????????
      +---------
HLXXX | FENYFGFN
       -YYXXR
        =====
        WRNYXG
       -WFRXXJ
        ======
          RNMYF
         -RWXXF
          =====
           LMNMN
          -EMXXG
           =====
           ?????

base: 13
letters: EFGHJLMNPRWXY
difficulty: medium
missing: P