????????
      +---------
NHQFL | HUPGHRPN
       -REEUG
        =====
         QFEHR
        -QREML
         =====
          UMHFP
         -UHRWG
          =====
           FGWPN
          -EWWHG
           =====
           ?????

base: 12
letters: EFGHLMNPQRUW
difficulty: medium