????????
      +---------
MRPGM | QMRWTWNP
       -PXQRP
        =====
         RWGGW
        -MRPGM
         =====
         NLTHPN
        -NLHEHM
         ======
           XRGTP
          -EMNWW
           =====
           ?????

base: 12
letters: EGHLMNPQRTWX
difficulty: hard