????????
      +---------
WTUFL | YJQNGUNU
       -WTUFL
        =====
        NULTQU
       -NETMMH
        ======
         UWUNMN
        -UEYGLF
         ======
          ULWQTU
         -UWMNLJ
          ======
          ??????

base: 13
letters: EFGHJLMNQTUWY
difficulty: challenging
hints: W << J, Q << M